Data Center Relocation

Data Center Relocation Guide

By: Peter Harrison

Friday, November 30, 2007 A LinuxHomeNetworking.com © White Paper

About The Author Peter Harrison has over ten years of data center experience in both the private and public sectors providing Internet and corporate services. He is a Cisco Certified Internetworking Engineer (CCIE) and currently consults on data center design and network architectures. He is also the author of the Linux Quick Fix Notebook published by Prentice Hall now available on Amazon.com. He was the founding president of PCJAM, Jamaica's first computer user group, and was the principal systems engineer responsible for the computerization of the island's tax collection and social security systems. He then sought new opportunities as the western Caribbean representative for a Fortune 500 pharmaceuticals firm and later became the international sales manager for a West Indian rum company. Before moving to Silicon Valley he ran Trinidad and Tobago's first industrial trade office to Latin America. Peter has since worked extensively in the Internet sector deploying large-scale data centers and Web sites. His extensive technical experience combined with his varied business background has helped him create this highly readable guide for project managers, techies, and their bosses. Peter also is the creator of LinuxHomeNetworking.com, a site dedicated to IT white papers and discussion on Linux, Cisco products and data center activities. In his quieter moments, Peter enjoys the art and literature of the Caribbean and Latin America. Long rides on his bicycle provide another guilty pleasure. Peter likes to relax with his family on short weekend trips to the many attractions of the San Francisco Bay Area.

Copyright © Peter Harrison 2002-2007, All rights reserved. Unless otherwise stated, the material published within this document is copyright of the author, Peter Harrison. No part of this document, including page design, interior design, cover design and icons may be reproduced or transmitted in any form, by any means, (electronic, photocopying, recording, or otherwise) without the prior consent of the publisher/author. As a sole exception, the author allows purchasers of this document to create a single printed version for their own personal, non-commercial use.

Disclaimer – The Website and Manual While every effort will be made to ensure that the information contained within this website and manual is accurate and up to date, the author makes no warranty, representation or undertaking whether expressed or implied, nor does it assume any legal liability, whether direct or indirect, or responsibility for the accuracy, completeness, or usefulness of any information.

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Table of Contents Chapter 1...........................................................................................................................................7 Why Relocate Your Web Site? .........................................................................................................7 When to Migrate From Virtual Hosting ...........................................................................................7 When to Migrate Between Data Centers ........................................................................................8 Factors That Affect Virtual and Self-Hosting ...................................................................................9 How to Analyze Migration Costs..................................................................................................10 Potential Increased Profits.......................................................................................................10 Net Changes in Monthly Expenses ..........................................................................................11 Capital Outlays .......................................................................................................................12 Conclusion.................................................................................................................................13 Chapter 2.........................................................................................................................................14 Preparing for Server Relocation......................................................................................................14 Data Center Selection Criteria.....................................................................................................14 The Relocation Project Plan........................................................................................................17 Coordination Preparation.........................................................................................................17 Customer Communications Preparation ...................................................................................19 Server Area Preparation..........................................................................................................20 Network Preparation ...............................................................................................................22 Server Preparation..................................................................................................................23 DNS Preparation ....................................................................................................................25 Transportation Preparation ......................................................................................................25 Conclusion.................................................................................................................................26 Chapter 3.........................................................................................................................................27 Post Relocation Activities ...............................................................................................................27 Activities During the Relocation...................................................................................................27 Post Relocation Activities............................................................................................................28 Appendix I ........................................................................................................................................31 Relocation Check ..........................................................................................................................31 Data Center Rating Form............................................................................................................32 ISP Rating Form ........................................................................................................................36 Cost Justification Work Sheet .....................................................................................................39 Potential Monthly Profit Improvement .......................................................................................39 Relocation versus Data Center Upgrade Capital Outlays ...........................................................40 Monthly Costs ........................................................................................................................41 Coordination Preparation Check Sheet ........................................................................................43 Customer Communication Check Sheet ......................................................................................45 Server Area Preparation Check Sheet .........................................................................................46 Network Preparation Check Sheet...............................................................................................48 Server Preparation Check Sheet .................................................................................................49 DNS Preparation Check Sheet....................................................................................................50 Transportation Preparation Check Sheet .....................................................................................50 Activities During the Relocation Check Sheet...............................................................................51 Post Relocation Check Sheet......................................................................................................52 Individual Server Worksheet .......................................................................................................53 Individual Server Worksheet (Part II) ...........................................................................................54 Additional Server Routes.........................................................................................................54 Network Enabled Applications List (netstat -a output) ................................................................54 Contractor Qualification Check Sheet ..........................................................................................55 Data Circuit Check Sheet............................................................................................................56 Vendor / Purchasing Check Sheet ...............................................................................................57 Post Mortem Analysis Sample Form............................................................................................58 Customer Information..............................................................................................................58 Incident Summary...................................................................................................................58 Incident Detail ........................................................................................................................58 Customer Impact ....................................................................................................................58

Root Cause Analysis...............................................................................................................59 Corrective Action Plan.............................................................................................................59 Appendix II .......................................................................................................................................60 How to Choose a Data Center ISP .................................................................................................60 Data Circuit Pricing ....................................................................................................................60 Internet Services.....................................................................................................................60 Non-Internet (Carrier) Services ................................................................................................61 Data Circuit Types......................................................................................................................61 Table A3.1 - Common Data Circuit Terminologies .....................................................................61 Data Circuit Provisioning.............................................................................................................62 IP Address Ownership................................................................................................................63 Routing Protocols .......................................................................................................................64 Border Gateway Protocol ........................................................................................................64 Table A3.2 - Common BGP Routing Terms...........................................................................65 Determining a BGP Autonomous System Number .................................................................66 Administrative Tasks Needed to Advertise BGP Routes .........................................................66 Conclusion.................................................................................................................................67

Introduction The commoditization of many aspects of IT infrastructure, from software and servers to Internet access and data storage, has created an explosive growth in the use of computers in day to day life. Now almost every business has considered or uses the Internet as a sales, marketing or operational tool. The supply and demand of IT services is therefore very fluid as the business and technology cycles change. The result is a constant reevaluation of IT costs and functionality with the server farm often being at the center of the analysis. This book focuses on the need to relocate a website of servers to a new physical location where the destination data center is managed by a third party. It covers common reasons for such actions, the factors to consider in choosing a data center, the actual server migration and post relocation activities. It is a short guide aimed at the busy professional who needs to be aware of the most important operational activities that need to be done and gives many concrete examples with explanations of many terms used in these types of projects. If you have any comments or suggestions about this document, please feel free to contact me via the LinuxHomeNetworking.com Web site.

Chapter 1

Why Relocate Your Web Site? Businesses that need to have a Web presence usually begin with a cheap virtual hosting provider (VHP) that constantly aim to reduce their costs via standardization. Each VHP web server potentially handles hundreds of web sites, with access to only a single type of application server, database, shopping cart, blog, web mail or message board forums software suite. Customization usually occurs through a standard web GUI interface which is usually geared towards altering the work flow features of the software and not its overall performance. Support is usually only given through instant messaging. For a simple website with the aim of providing supplemental information to newspaper or web advertising then basic virtual hosting services, which start at about $10 per month, should be sufficient. The cost advantage of this service declines as you require additional high end services or customization. The challenge is to determine the point at which do-it-yourself self-hosting becomes more attractive than using a VHP. If you decide to migrate to self-hosting, the next challenge is to determine the daily tasks you will need to do yourself and those you intend to outsource to third party service providers. You will constantly find yourself adjusting these responsibilities for a variety of reasons and you may even have to consider migrating your Web site between physical locations to achieve these goals. Always remember that the decision to migrate your Web site should be strictly based on business needs. Embark on it when your service provider threatens the future growth of your company. Plan we ll, only use proven stable technologies, go slowly, have a backup plan, inform your customers and minimize your exposure to downtime risk at every step of the way. This chapter will describe a number of scenarios in which physically migrating a Web site can become desirable and will cover ways of determining a financial justification for doing so. The rest of the book will cover the logistical problems of data center selection and preparation, planning, the migration itself, testing and post migration procedures.

When to Migrate From Virtual Hosting The lack of support for customization is the VHP's greatest weakness. There are many cases in which this can become painfully obvious. Here are some typical examples: 1. Expensive Shopping Carts: Sometimes you want visitors to be able to search your website for a list of available products by name, by category, in a particular price range or from a specific manufacturer. This requires web pages to be generated dynamically using application server software that queries a database. This can cost about $100 per month, and if you need the person to buy the product using a shopping cart, then the price can reach as much as $150 for an entry level service. In comparison, you can lease a dedicated server for $200 per month in a collocation data center and if you choose to use Linux, your software procurement costs would be negligible. Self hosting in this scenario can become desirable if you already have a capable IT staff with sufficient resources to complete the project wi thin your budget and on time. 2. Unpredictable Software Updates: With virtual hosting you are dependent on your service provider to provide software updates or patches to fix security, performance or functionality problems. There may be delays in completing your requests especially if you are one of many customers on a server. The service provider also has to ensure that the upgrade won’t affect any of the other websites and this can add delays. Additionally, there may be times when you need to implement software that needs to be installed external to your home directory that isn't supported by your hosting provider. Examples of this

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Relocating Servers Between Data Centers -

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include a new database product and centrally managed server logins using LDAP. In these cases the justification for self-hosting becomes even stronger. 3. Server Overload: With hundreds of websites on a server, you run the risk of slow response times due to one of the URLs owned by another company suddenly becoming popular. The cause of this latency is often difficult to determine, and correct especially in a shared environment where you don't have access to many systems tools. 4. Lack of Redundancy: Many businesses rely on a web presence for the majority of their revenues and cannot afford to have extended periods of downtime. With the use of load balancing devices it is possible to spread your web hits across two or more servers. The load balancer regularly probes your servers and automatically steers traffic away from any server that appears to be malfunctioning or down. This is a useful offering if you need to take an application offline for maintenance. Many virtual hosting providers don't offer such a service to individual customers. 5. Inflexible Security Services: You may want your applications to run on unique TCP/IP ports and be accessible only to certain IP address ranges or you may want communications with these ranges to be fully encrypted over a virtual private network (VPN). This will usually require some form of VPN or firewall service that your provider may not offer. This requirement may open a vulnerability to other web sites. For example, allowing FTP access to the virtual server potentially opens the door to unrestricted file transfers to all sites on the server that share the same IP address. This may be viewed as a security risk for your neighbors. If you don’t want to risk this type of exposure, then consider self-hosting. 6. Restricted Supplier Management: You may require highly customized reporting or have complicated inventory listings which have to track parts, sub assemblies and finished products. There may be the need to link your shopping cart order entry system, which contains all your customers' credit card information, with the inventory system of a supplier. Your virtual hosting provider may be able to do this, but it may expose more of your business to this provider thereby increasing your risk. 7. Poor Site Availability: All service providers need to schedule maintenance of their servers, but the time they choose may be inconvenient to you. They may also have unreliable equipment that adversely affects your site's performance and may not have adequate backups of your data in the event of catastrophic failure. 8. Insufficient Language Capabilities: VHPs often provide technical support in only a few languages. If you can't get adequate support for billing, engineering, and customer care services in your preferred language, then an in house solution may be better. There are many other scenarios in which a VHP may become undesirable but these examples have provided some of the main ones you will most likely face. The next section discusses how migrating existing self-hosted Web site can have very different issues than those associated with migrating from a VHP.

When to Migrate Between Data Centers The decision to migrate an existing self-hosted site to a new physical location often has very different criteria than those associated with migrating from a VHP. This is because the desire for improved services extends beyond an individual server and encompasses the entire data center facility. Here are some common reasons for considering this option whether the facility is owned by your company or provided by a third party. 1. Poor Cooling: As a data center becomes increasingly occupied the thermal load it needs to handle becomes greater. Your service provider may not have adequate computer room air-conditioning (CRAC) units to cool the entire floor space and may be unwilling to upgrade due to financial constraints such as a lack of funding or an anticipated inadequate return on investment. There may also be cases in which your section of the floor just has poor circulation and other better ventilated

Why Relocate Your Website?

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locations within the facility are too small or geographically fragmented to comfortably accommodate your servers. 2. Unstable Power: This can cover a variety of factors from fluctuating voltage, insufficient UPS backup, ignored preventative maintenance, insufficient circuits in your server area and nonredundant power feeds to your server area. In all these cases, both the status quo and upgrades of the service could threaten the reliability of your electricity supply. 3. Insufficient Power: As servers become smaller and more powerful their demand for power can become enormous. It is now possible to install up to 80 servers in a standard 19" x 72" x 36" rack with a power load of over 20 kilowatts, that's as much as 20 microwave ovens running 24x7. 4. Unsuitable Physical Security: You may feel that this is limited to access to your server area, but it should also include accurate entrance logs whether they be manual or electronic, video recording of physical access to your area, the use of unique keys for all cabinets and customers, and the deployment of suitable fire detection and suppression equipment. You may want to consider migrating if any of these factors don't meet your requirements. 5. Inadequate Floor Space: The most obvious shortcoming is a lack of floor space but people often forget that, in a data center owned by the business itself, floor space used for servers could be better used for other purposes. For example, a server room located in a downtown office where rents are high may be more cheaply located in an industrial area nearby. 6. Unreliable Data Networks: The data center you use may have a number of connectivity shortcomings. The internet service providers (ISPs) used may be unreliable, the networking gear could be poorly maintained or over-utilized, staff could be inadequately trained increasing the risk of human error, cabling work could be sloppy, maintenance work that could cause outages may be unannounced or fall outside your desired time frame, and the equipment used my be obsolete making it unable to provide desired features that could improve your site's performance. 7. Using a New ISP: Sometimes the Internet IP addresses your site uses came bundled with the data circuit provided by your ISP. If you are forced to use a new ISP, you may be forced to change your addresses. This can be a complicated problem which will require many of the steps used in a physical relocation. It is for this reason that some IT managers may use the opportunity to consider a complete re-evaluation of the data center strategy which may include a migration of servers to a more suitable data center. 8. High Cost: If your data center meets all your needs and yet costs more than a comparable facility nearby, then it may be time to consider your alternatives such as negotiating better monthly rates from your existing provider or simply go to the competition. Be especially careful if the unsuitable data center is your own. Though the cost of making improvements to your data center may be much greater than the cost of moving the servers to a data center owned by a third party, the recurring costs there could be more than the ones you currently incur.

Factors That Affect Virtual and Self-Hosting There are some relocation needs that affect companies that do either virtual or self-hosting. 1. Data Center Consolidation: Companies often inherit data centers when they purchase other companies. Servers and Web sites can be repurposed or retired to reduce overhead costs and management complexity. Sometimes data center space can be used more productively for another purpose. 2. Disaster Recovery: A disaster can debilitate your company especially if all your IT resources are in a single location. Catastrophes can be caused by huge events such as hurricanes, floods, snow storms, and earthquakes, or they can be more localized in cases such as hazardous spills and lightening strikes. Even the simplest things can have a huge impact. Leaking water pipes in floors above your data centers, faulty fire alarms that force complete building evacuations, employee

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sabotage triggered by layoffs, and overloaded circuit breakers can all contribute to downtime that could be avoided by having a failover data center. 3. Changing Customer Demands: Increased competition and the opening of new markets can shift the demographics of your customer base. This may require the use of additional IT tools that are more efficient, less costly, have better performance or have more features. Your existing facilities may not be able to accommodate these increased demands and you may find yourself having to expand beyond your existing boundaries. 4. Cost Reduction: New technologies and business processes can reduce many IT recurring expenses but can also require relocation of your servers. For example it may be possible to outsource some back office operations such as monitoring, backups and networking services more cheaply in another facility. Also, as mentioned before, some overhead costs can be lowered by reducing the number of data centers or servers you operate. 5. Failed Outsourcing: Your IT business partners may fail to meet your disaster recovery, performance and cost expectations forcing you to seek alternatives such as new outsourcing providers or to take the work in-house where you have more control. 6. Obsolescence: Outdated facilities can increase your recurring maintenance costs but they can also not meet industry standards or government regulations. In such cases relocation may be cheaper than upgrading. The reasons for relocating can be complex and should be approached carefully. The cost justification, and risk analysis for doing so can be difficult to quantify. This will be addressed in the sections to follow.

How to Analyze Migration Costs If you decide to do self-hosting, you should also consider its consumption of your business resources, namely time, talent and money. The financial cost of the equipment is obvious, but there are resource costs related to installation, training, staff shortages, consulting, security and long term maintenance. With an existing IT staff, the strain would be less but if the company is small the price of customization could be a high proportion of your business overhead expenses thereby making self-hosting uneconomical. If you are a small company with limited IT staff, or you have capable staff that would be better utilized expanding the business, then it may be best to adjust your requirements to fit the services offered by a virtual hosting provider. You can reconsider self-hosting in future when the customization needs of the company are more pressing. At this time create a pilot project using only the most essential customization and if successful, gradually migrate over to a production version of the pilot site. Convert your pilot to a general testing and staging area and then add modifications to the production site when you are satisfied they work. Sometimes businesses should accept the fact that self-hosting, though desirable, may be beyond the budget and capabilities of their organizations. Switching to a more expensive fully managed hosting provider that specializes in customizations may have to be considered in such a case. Migration cost analysis should focus on three broad areas; the potential for increased profits, expected reductions in monthly expenses and the capital outlay to carry out the migration. These are covered next.

Potential Increased Profits Most businesses try to forecast their profit growth. As part of these plans they purchase software that can facilitate expansion into new markets or save costs and they may even consider testing the limits of existing IT resources to achieve these goals. Sometimes the driving force to invest in IT isn't profit growth, but guaranteed revenue. Calculating the potential lost profits by not investing in information systems can also be a deciding factor. This can sometimes easily be calculated by determining the impact per hour of downtime on sales and the expected amount of downtime during


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the financial year due to inadequate resources. Once you have this information it becomes easier to calculate the expected return on the IT investment in terms of increased profits or liberated cash flow.

Net Changes in Monthly Expenses Net expense reductions can be calculated as the eliminated monthly costs that stem from the migration subtracted from the forecasted monthly expenses in the new facility. Recurring expenses to consider in both the new and old facilities should include the following: 1. Maintenance Contracts: Most people primarily think of computer equipment maintenance but if you manage your own server room there will be many other maintenance figures to consider. The upkeep of CRAC units, security systems, UPSs, standby generator plants and fire systems as well as the retention of janitorial and security guard services may need to be included. You may also have to consider additional IT services such as networking, DNS and database services. 2. Power: Electrical costs in your own server room may be directly tied to actual consumption, but third party data centers usually charge for power by the number of circuit breakers and/or power outlets you decide to use. 3. Cooling: As power consumption increases so do your cooling requirements. Many third party data centers include the cooling cost into their power charges unless your installation requires major expansion of their facilities. In this case you may be expected to either directly contribute to the expansion or commit to a long term contract. 4. Floor Space: In your own server room this is a fairly straightforward cost. With a data center provider you may be offered floor space as a full computer cabinet or only part of it. In some cases you may be offered an existing caged area which may not exactly meet your needs or you may have to sign a long term contract before the facility will agree to creating a custom space for you. 5. Bandwidth: When you convert to self-hosting the cost of your Internet connection will most likely become more variable in nature as it will fluctuate with the amount of bandwidth you use each month. Appendix II discusses many of the factors in selecting a data center ISP in more detail. 6. Staffing: Self-hosting will inevitably require additional staffing resources. You may have to hire additional employees, either as staff or contractors, or you may have to train existing staff members continuously and raise their salaries to match their new skill set. In the event of data center consolidation you may have less staffing needs too. 7. Security: Physical security expenses will largely be covered under various security system maintenance contracts and the hiring of security guards. If you are using a third party data center, then this may be included in your floor space expenses. Data security is similar. This may be provided as a contractual service or handled by yourself; it may also be included in one or more maintenance contracts. Your budgeting should include the monthly cost of backup services, replacement tapes or other media, off site storage, software update and anti-virus services, and firewall and intrusion detection services. 8. Travel Time: It may seem trivial, but always try to determine the cost of commuting to your new server location. Most website maintenance can be handled remotely, but wh en things go wrong or you have new physical installation work to do the cost of travel delays can become significant. You may decide on a cheap data center located an hour away by car but if a device begins to intermittently fail, sometimes during rush hour, the duration of outages can jump dramatically and so will the cost of lost revenue. 9. Equipment Leasing: Migrating to a new facility may also require leasing additional hardware to accommodate the move. Some data center providers will also throw in equipment leases at favorable rates to get your business but they won't allow you to leave with the equipment should you decide to go to a competitor. It may also be a good time to renegotiate the

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replacement of existing obsolete equipment with newer models. This could affect your operational costs at the new location and should be factored into your calculations. 10. Systems Development: In a virtual hosting environment the software used to make the management of your site easy is rolled into the cost of the service. With self-hosting this could become an additional expense as you may have to begin a continuing project to provide the same features to your internal users. With the management of your website more firmly within your control you may also find yourself having to integrate its operation more closely with other business systems within the organization. This could add additional hidden expenses to the project. Always try to separate the migration savings from the additional expenses of this type of work. It is easy for a profitable change of web service providers to be weighted down by the allocation of expenses not directly related to the activity. Subtracting the net change in monthly expenses from your profit projections will provide an overall expected monthly cash flow from the project. This then can be used to justify the one time capital outlays required to get the job started.

Capital Outlays There are a number of one time costs that will be encountered at the beginning of the migration that you will have to account for. These include the following: 1. Leasehold Improvements: You may have install the infrastructure to support your web site being moved to the new location if you don't have it already or if it's not supplied by your new hosting facility. This could include additional power, cooling, fire systems, backup systems, UPSs, computer cabinets, racks and shelving, fencing, patch panel cabling, standby generator plants, cameras, keyless entry systems and raised flooring to name a few. 2. Transportation: The cost of physically moving should also be included. You could use a professional moving firm or you could rent a truck. In the latter case you may also have to rent secured shelving, on which the computer equipment will be placed, and mount it in the truck. You may also be forced to rent or buy boxes in which to transport your equipment and other miscellaneous items. 3. Overtime: Most web site migrations are usually done after business hours at night and on weekends which may require the payment of shift premiums or additional vacation time to compensate your employees for the inconvenience of the working on the project. 4. Staffing: In the event of data center consolidation you may be faced with increased staff costs due to layoffs or rapid attrition which may demand unexpected re-hiring costs. Relocation or expansion activities will also increase staffing costs due to the need for increased numbers of employees. 5. Contractor Fees: Contractors may not just be used to install leasehold improvements but they could provide services specifically for the move. These could include project management and data migration and recovery skills your organization may not already have. 6. Training: This is a frequently over looked expense that is often rolled into monthly costs, but you may require your staff to get several foundation training courses to allow them to handle the new tasks they will be expected to achieve. Some people will treat it as a recurring expense, others may want to account for it as part of the moving cost. 7. Equipment Acquisition and Temporary Leases: If you are moving between data center providers you may be faced with incompatible equipment at the new location. For example, the data backup formats used at the old and new facilities may be different forcing you to lease a tape backup unit just in case you have to restore data in the event of a server failure during the migration. You may also be forced to use new servers which may add unexpected problems. The software you currently use may be incompatible with newer technologies or you may not have any


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remaining staff that knows how to reinstall your existing software on the new hardware. This could force you to purchase brand new versions of the software before you can proceed. 8. Cleanup Costs: You may have to restore the original server area to its original condition. This could require the removal of racks, cabinets, raised flooring, power feeds and networking gear. You may have to get professional cleaning help not just from janitorial services, but also from technical professionals who are capable of decommissioning IT infrastructure. 9. Penalty Fees: Some contracts have early termination fees and these may apply to some of your IT infrastructure. Be aware of the cost and plan your migration to possibly limit the extent of your obligations. 10. Movers Insurance: You may have to insure some of your equipment against damage that could occur during the relocation. This may add further delays and costs. Once you have an idea of the capital investment required for the migration, you can compare it with the expected returns in the form of monthly savings or increased profitability. If the return on investment is better than the interest you can get at a bank, then the project is probably worthwhile. Even if the project has marginal profitability, it may be justifiable on the basis of making your company more responsive to market pressures especially if you are moving from a VHP. This type of financial analysis is often ignored and yet it is so important in making a reasonable decision to switch service providers. The extra time it takes to do it could save your company thousands of dollars in the long run.

Conclusion The decision to migrate your Web site can be difficult. You have to weigh the benefits of increased control, improved flexibility and reduced costs with that less complicated management and technical skill requirements. Whatever you choose to do, plan carefully. Always get a professional opinion, even if it's informal, and always be aware of the potential risks of the decision you make. If you decide to do it, Chapter 2, "Preparing for Server Relocation" will provide a lot of guidance in completing a successful project.

Chapter 2

Preparing for Server Relocation The rationale for deciding to relocate or consolidate data centers was discussed at length in Chapter 1 "Why Relocate Your Web Site?" This chapter explains in detail the criteria you should use to select your new data center and create a project plan. A lot of information will be covered and the numerous action items mentioned are included in the work sheets in Appendix I to help make the process easier.

Data Center Selection Criteria There are two broad categories of data center providers. The first only supply computer room floor space, access to an ISP, basic monitoring and power. These are called collocation providers. The second group provides more comprehensive management that may include all possible IT services related to your site including systems development. These are called managed hosting providers. There are a wide range of varying service levels in between and the interpretation of the terms within the industry can often be very loose. Always request a very specific list of the services your data center provides as part of your selection process. As expected, the selection of a suitable data center will play an important role in any data center or web farm relocation project. There are many factors related to the facility and its services that need to be considered that are often overlooked. These include: 1. Location: The data center should be positioned away from zones at risk from natural disasters such as flooding from rivers and dams, hurricanes and earthquakes. It should also be no closer than a quarter kilometer away from major highways and railroads to reduce the evacuation risk from toxic spills. Locations close to hazardous production facilities and aircraft flight corridors should be avoided. Your employees may have other personal interests in the location such as the presence of reasonably priced housing nearby, recreational attractions in the area, access to public transportation, and the availability of amenities such as schools and parks in the neighborhood. You should monitor how traffic patterns affect the ease of accessibility to the site to see whether they are unsuitable. The immediate vicinity of the site is also important. Rainwater should drain away from the building and then off site to prevent localized flooding. In high security environments the building should be surrounded by embankments and perimeter fencing, reducing the risk physical attack. 2. Communications: The facility should have access to multiple ISPs with the cable entering from different points of the building. This reduces the risk of outages due to a technical failures as well as construction and landscaping accidents. Verify the roof access rights in the event you need to have a satellite or microwave line of sight antenna installed. It is also extremely important to visually verify the type of connectivity you have. Be certain that both the ISPs that enter the building and the types of data circuits they can provide are suitable. Don't sign a contract with an ISP where you are held hostage to unsuitable or otherwise inadequate connectivity. This is discussed in greater detail in the appendix. 3. Electrical: Power should be supplied from multiple feeds from different substations. The facility should also be able to run without interruption if its largest standby generator or UPS are offline for maintenance. Ensure that the building has sufficient excess capacity to handle future growth. In large facilities, the UPS feeds a network of power distribution units (PDUs) to supply each section of the floor with a series of circuit breaker panels. Make sure that every rack or cabinet you intend to use has access to outlets from at least two PDUs and that each PDU is operating at no more than 45% so that it can handle the full load of the other one if it fails.

Appendix II - How to Choose a data Center ISP

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Request a history of outages or other irregularities in the feeds from the site's utilities and ask how you'll be notified by the facility of any electrical maintenance work to be carried out by either themselves or their providers. The facility's staff should also be automatically notified by monitoring equipment of any disruptions in the power supply to the area. Ask how quickly the generators respond to an electrical outage and how long the UPS batteries can last. Inquire about whether the UPSs have ever supplied the full load of the data center and when last the system, including the batteries, was last maintained. Standby generators can be regularly started without revealing any apparent problems, ask whether testing includes the use of a load bank to simulate the power consumption of the data center. Investigate how frequently the equipment is tested and how often it is maintained. Verify that the power per square foot that the data center can provide meets your needs. Racks of densely packed servers and data storage can be power hungry. 4. Cooling: Most data centers try to maintain a 75F/25C air temperature, verify this. On your plant tour be on the lookout for computer room air conditioning (CRAC) units that squeak or rattle loudly as it could be a sign of poor maintenance. Condensation from CRAC units should be drained away immediately through piping, be on the lookout for water leaks. 5. Security: Verify that there is 24/7 security enforcement. This should include offices and common areas being isolated from the data center floor, mandatory visitor/employee registration or electronic ID access and interior/exterior video surveillance. Some data centers also link visitor ID cards with a person's biometric information through the use of a palm reader. This helps to deter ID card fraud. 6. Fire Protection: Not only should there be smoke and heat detectors, but they should be linked to an alarm panel that graphically shows the location of the fire on the building's floor plan. The first line of defense should be a gaseous system that suffocates the fire by displacing the oxygen in the air. These systems are less damaging than water based ones but they are usually designed for fires of short duration. Larger fires will often require a pre-action water based system. Here the pipe lines are pre-filled with pressurized air to reduce the risk of flooding during normal operation. Water only enters the piping after an alarm signal has been detected, then the sprinklers release the water only after a pre-defined temperature has been reached. False alarms are minimized by requiring two events to occur before the system is activated. This is an industry standard method of fire prevention and it should be on your checklist. If your data center is situated on raised floor tiles, you should ask whether there are liquid detectors underneath. This helps to prevent problems due to extinguisher and CRAC unit leaks. Also in this case, make sure that the cabling lies in trays above the floor out of harms way from minor flooding. If possible, the server area should also be isolated using fire proof doors. 7. Network Connectivity: Not all data centers will provide you with Internet connectivity. Some will only have a demarcation point where ISPs have placed their equipment. You will then have to contract with the ISPs to extend a data circuit to your server area. Connectivity can become more complex than it first appears. There are different types of data circuits requiring varying types of adapters on your network equipment. If you require only one link, then you'll need to configure a single default gateway on your network equipment to get to the Internet. When multiple links are required, you'll need to configure a dynamic routing protocol on your network equipment. This will automatically calculate which of the many links will get to the data to its final destination most quickly. It can also be used to bias traffic to and from your web site on the cheapest ISP link and will automatically fail traffic over to the remaining ISP circuits if one of the other circuits fail. Detailed discussion of typical network connectivity issues usually requires the services of a network engineer and is beyond the scope of this chapter. Appendix II will cover many frequently used terminologies and scenarios to help you evaluate your options better. 8. Network Monitoring: It is often taken for granted that your data center provider continuously monitors its equipment for failure. Ask about the frequency of the checks. A polling cycle of five

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minutes or less is generally acceptable. Also ask about the types of checks done, ICMP (Internet Control Message Protocol) or "ping" tests only check basic network connectivity and server response. The facility should also use SNMP (Simple Network Management Protocol) to track CPU, memory, error and data throughput rates. It is possible for SNMP enabled systems to send notifications, or "traps", when components fail, or a predefined event, such as high CPU usage, occurs. This information should be fed into some form of a job ticketing system that will ensure that the problem is fixed quickly. Ask about the number of failed polls that will trigger an alarm and whether they too will automatically generate a ticket. 9. DNS: Ensure that your data center uses multiple DNS servers, behind different firewalls, in multiple locations to prevent your web site from being affected by one of the servers going down. Some facilities will provide not just caching DNS for the exclusive use of your servers, but also authoritative DNS services to handle Internet queries for your Web domain. With authoritative services, ask about the procedures for updating DNS, the lead time for requesting changes and the format of the DNS data the provider will need to enter it into their systems. 10. Customer Support: Ask about the availability of a web portal through which you can view statistics, billing, contact, and server information related to your site. Also ask about the times during which scheduled maintenance is done and the types of notifications that are provided. Request a summary of escalation procedures used when problems occur and whether there is a formalized means of documenting and permanently fixing problems. From time to time you may need simple services such remote hands on help in rebooting a server or changing a backup tape. Ask about the availability of such services and possibly more complex ones through an as-needed contractual or longer term retainer based agreements. 11. Data Backups: The backup system you are using at your current location may be different from the one used at the new facility. This could be the source of difficulties if you have to restore historical data during or after the relocation due to server failure or human error. Verify whether the new facility can handle data backed up using your software on your backup media. If not, you may have to invest in data conversion services with a third party. Good backup services usually store data for a predetermined period of time before reusing the media. They should also store most of the data at a secured secondary facility. This protects the data from catastrophic events at the main data center. Verify that this type of extra data security exists. 12. Floor Space: For improved safety, the data center floor should use anti static tiles to reduce the risk of electrostatic shock damaging your equipment components. Water pipes, steam lines, bathrooms, kitchens and other sources of moisture should all be located a safe distance away. Also, they should not be directly above the area. You should also determine whether the location has sufficient floor space to handle our current and future needs. Some facilities allow you to reserve the area immediately surrounding your server area for future expansion. 13. Facility Cost: This factor can present itself in many different ways to include pricing for bandwidth, power, cooling, security, floor space rental and custom services. It is a good idea to determine what the total costs would be over the time period you expect your current website architecture to be used as the costs can be presented as recurring and/or one time expenses. Lower recurring costs can easily give the perception of cheaper operating expenses but the price may become unfavorable when higher setup fees are taken into account. Remember that this is a perfect wish list. The data centers in your vicinity may not meet all the criteria but the list should allow you to reduce your final candidates to a manageable number. Data center selection is only the first phase of the physical planning for the relocation and will largely be the responsibility of your facilities and networking teams. The work that will follow will demand a lot more from your IT support staff and will have to be carefully coordinated as we will see in the following sections.


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The Relocation Project Plan Detailed logistical planning of all the steps related to the relocation needs to be started well in advance of the deadline date. You'll probably need to start with a number of meetings to inform each of the affected groups about the project. These will have to be followed by project planning meetings in which roles and responsibilities are assigned and progress reports given. As the deadline date draws near or as the complexity increases, be prepared to schedule daily and sometimes twice daily meetings to achieve your goals. There are many aspects of the migration that need to be thought about prior to arranging the first meeting. Some of the most pressing ones will now be discussed.

Coordination Preparation There are a number of things that need to be considered prior to setting up specific functional groups for each aspect of the relocation. These are discussed next. 1. Project Management: Have a single overall project manager for the activity. If the project starts to become complicated invest the time in tracking it with software tools such as Microsoft Project. Spreadsheets can track static information well but do relatively poorly in monitoring the status of dynamically changing deadlines. Constantly changing priorities can be disruptive. Plan to include deadlines after which time no further changes may be made. Set up meetings on these days to determine whether the project or sub-project should be aborted, continued as planned or given a preparation time extension. 2. Roles and Responsibilities: Create an activity checklist that assigns each member in the team clearly defined roles and time frames in which to get activities done. Specifically assign someone the task of keeping track of the problem equipment that may fail. The project manager will inevitably be distracted by other events and this will help to ensure that forgotten technical issues don't threaten the success of the migration. There should be persons to lead transportation, networking, server shutdown/startup, application testing, customer communications and the locking of the doors at both the old and new facilities once the relocation is complete. An often overlooked role is one of the "gofer", someone who will go for anything that you have forgotten. It could be to buy cables you forgot to order, pickup catered food, or to find the software CDs that "must be somewhere over there in those boxes". Remember to give them some small reward when it's all over as it is one of the most thankless jobs. 3. Disaster Recovery Team: Have a group of persons assigned to disaster recovery. It should include staff that is familiar with systems administration, database administration, networking and backups. These persons don't necessarily have to be sitting idly by waiting for something to break. They can still play important roles in the preparation steps, but should be given a reduced workload during the relocation itself that will allow them to dedicate their time to such activities. 4. Procedures Documentation: There are three types of procedural documentation that will have to be up to date. The first relates to those used by your existing systems which won't change as a result of the relocation. The second would obviously be the documentation for systems that will change after the project is over. The third type is equally important. It is the documentation of the steps each participant is expected to do during the relocation. As part of the definition of the roles and responsibilities, some participants will need to have a detailed task list to help prevent them from making errors. These would include step by step commands that a technician or engineer would need to execute as part of the process. This person can cross this activity off their check list when the tasks are completed for better control of the change process.

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5. Interpersonal Communications: Make preparations to have a permanent conference bridge open so that all members of the team can be better coordinated in the event of a crisis. Make sure all active participants at the time of the migration all have mobile phones on their person. 6. Participant Lists: Have a complete list of participants in the relocation. This should include their work, mobile, and if possible, their home phone numbers. It should also include contact information for all third parties involved with the activity such as movers, technicians and contractors. This list should be distributed to the entire team. 7. Contractors: You may need to use contractors to do some of the work your staff may have neither the time nor ability to do. They should be qualified, experienced and authorized by the manufacturers they represent. Contractors should also use the correct tools and be able to test the quality of their work. A check list for contractors is provided in Appendix I. 8. Vendors / Purchasing: One of the most difficult aspects of a data center move is the coordination of purchases from your vendors. There are many things to track. Items have varying delivery lead times, you may forget to order something, items may have to be returned or replaced, and deadlines may shift. A sample purchasing check list for purchases is provided in Appendix I. You may want to adapt it to a spreadsheet format to make it easier to share with your vendor. 9. Inventory: You will have to do a complete inventory of all the equipment to be moved. This will also have to include "before" and "after" data related to the network connectivity and physical location of each device. The actual required information for each type of equipment will be covered later in the chapter and accompanying check lists are provided in Appendix I. Record this information in a database if possible. It will allow for very flexible reporting including individual status and data sheets for each device. Not everyone will have access to the application, so ensure that it has the capability of creating word processing or spreadsheet versions of the reports for more universal distribution. 10. Equipment Leases: Some relocations cannot afford any downtime at all and you be forced to purchase or lease equipment to create a duplicate environment at the new location. You may have to assign the acquisition of such equipment to a team lead and adjust your budget accordingly. 11. Relocation Date and Time: Determine the best time for the migration. If it takes place at night, and/or over an extended period, allow for overtime, catered food and possibly compensatory time off. For nighttime moves, make sure your daytime skeleton staff is capable of handling regular business issues and can relieve the night staff of some of the technical problems that may arise. Verify that there won't be delays due to rush hour traffic or road maintenance at the planned time. 12. Failed Equipment Identification: Have some way of marking equipment that isn't working. A brightly colored sticky note stuck to a server and the rack or cabinet in which it is located is usually sufficient. This makes it very easy to identify broken equipment from a distance. Make everyone aware of this process. 13. Plan of Retreat: Create a plan of retreat in the event that things go dreadfully wrong. Create a shortlist of scenarios during the actual relocation under which the project cannot go forward. Have some mechanism of informing everyone of the decision. Create a list that defines the sequence in which servers should be returned. Also identify a point of no return at which you cannot roll back your changes. In this case create a minimum list of servers that need to be functioning for the website to be adequately operational. If things go wrong, ensure that these servers are functioning correctly. 14. Practice Migrations: Plan to do a practice relocation of some non critical servers to see whether you are really prepared for the full scale operation. These are some of the general preparatory tasks that need to be done and you may have to add a few that cater to your unique needs. It is a good first step before proceeding with more specific plans.


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Customer Communications Preparation Notifying your internal and external customers of the expected changes will be critical to the success of the project. Consider these activities as part of the plan whether the relocation is successful or not. 1. Customer Notifications: Provide ample warning of the impending activities so that your customers can plan for the change. 2. Targeted Messages: Have a single message with varying degrees of detail for each customer group depending on their information needs. For example, web surfers may need to know that your site may be unavailable for maintenance for a specific time period but business partners may need to know about any new procedures the change may create. The message should explain the reasons, expected features and associated benefits of the change. Plan to have this message delivered in person to your most valued customers. Make sure it is delivered to all internal departments that could be affected by the planned activities. 3. Contingency Planning: Create a communications plan in the event of a failure. Here is a list of guidelines I strongly recommend be followed: >

Create a web page or blog to provide updates on the progress of problem resolution. This should also include contact information for your crisis spokesperson.

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Provide sufficient information to make all affected parties aware that you're taking the matter seriously. Describe the extent of the problem and a statement that addresses any possible concerns of those who may not be affected.

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Update this page at predictable stated intervals even when there's nothing to report. Significant events outside this schedule should be reported immediately.

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If the issue has public visibility, have a video or audio clip of the company President/CEO making a factual statement about the matter that expresses remorse, and a promise to have quick resolution.

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Create lists of potential questions, answers and discussion points for those parties that are affected, not affected, business prospects, the press, and analysts.

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In times of crisis, personalized verbal assurances and updates can be valuable. Attempt to give every customer a personal phone call. Use the Q&A discussion points. The callers will have to be prepared to take some abuse. Have them allow the customers vent while sticking to the script. Senior management should make some calls too to gain first hand understanding of the pain everyone is feeling.

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Don't forget to contact customers that are not impacted. Focus on the most important ones to provide them with personalized verbal service assurances. Send e-mails to all other nonimpacted customers with statements about service continuity.

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Have senior management call important sales prospects to provide justifications to choose your company in spite of the disruption.

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Use a company wide all-hands meeting to provide a first hand situation status. It should be brief as there will be lots of work to do. Provide regular email updates to employees via email.

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You should also have someone monitoring the web media and blogosphere to get feedback on what people are saying, and who's saying it. When comments are necessary, simply reference your updates web page. Use this updates page to correct misstated facts neither making excuses nor being defensive. Only authorized persons do such limited commentary on blogs.


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>


Contact key press and analysts. They will appreciate hearing directly from you even if they remain highly critical.

4. Lessons Learned: Some aspects of the migration may fail and documenting the issues can lead to much better experiences in future. Develop an easy to use post-mortem template that can be used to document any failures related to the migration. It should include the persons involved, dates and times the events occurred, reasons for the failure, error messages, the final solution and steps that will be taken to prevent the recurrence of the problem. This information should be made available to all members of staff involved in the migration and to customers who may demand detailed explanations of the cause of disruptions. The establishment of clear channels of communication with your customers is always important but especially so during projects of high risk. Always include them as part of any relocation plan to ensure a more complete success.

Server Area Preparation The health of your server farm depends on the quality of your physical infrastructure. A poorly prepared area can cause unacceptable delays and even a complete site shutdown. Follow these steps to reduce your risk. 1. Power Management: Your servers and disk storage will consume the most amount of power in your environment. Do an audit of the power consumption to determine how much you will require in the new location. Get a total figure and an estimate of what you expect to consume per rack or cabinet. Verify that the servers in each cabinet or rack won't overload the power circuits supplying them. Some power hungry devices may need unusual voltages or electrical connectors, double check this information ahead of time. Make sure each rack or cabinet can receive power from redundant PDUs and that there is adequate excess capacity on the PDUs to support not only your server farm but also the failure of one of the PDU units. Have the facility's management prove that you are getting UPS protected power in your area. It can be very frustrating to arrive at the new facility to discover that the server power cords used at the old location are too short for the racks in the new one. The problem usually occurs when converting from fixed racks to ones in which the servers are mounted on rails. This allows you to slide the servers out into the aisles for better access but requires cables that can stretch the distance. Verify that you have sufficient quantities of adequate cables. 2. Cooling: Verify that the area has an adequate number of CRAC units to cover your anticipated power load. The rule of thumb is that each watt of power consumed by a server requires a watt of cooling. Once the migration is completed you'll have to test air temperatures and humidity to ensure they meet the requirements of your equipment. In raised computer room flooring, hot air is extracted from the room, chilled and then returns to the server area under the floor blowing up into the cabinets through vents in the floor. The floor under the tiles should therefore be clean and generally clear of obstructions such as cabling and ducting. If possible baffles can be placed under each CRAC unit to guide the air flow in the direction of the cabinets it needs to cool. In some cases the floor under the cooling zone of the unit may need to be sealed off to force the air only to the required cabinets. You may also find yourself in a situation where the overall cooling requirements of the server farm are within the specification of your combined CRAC units but certain concentrations of servers within the farm could overtax the capacity of individual units. Plan to spread these high power density racks across the server floor to help balance the load across all CRAC units. 3. Labeling: This is very important. Ensure the power outlets are labeled with the PDU and circuit breaker number. This is especially important for systems with dual power supplies that should be plugged into separate power sources. Make sure power cables are labeled with the name of the server at both ends too.


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Make provisions to have all servers labeled on the front and the back to reduce the risk of incorrect cabling and likelihood of making a mistake with a hard (power cycle) reboot in the event of an unexpected server failure. Also make sure that all network cables are labeled at both ends. How do you start to number? Numbering schemes for cabinets and racks are usually straight forward. Split up the server area into zones serviced by the same patch panels or switches. Each zone will have a number of rows of racks and/or cabinets. A location number such as 111-4 could mean zone 1, row 11, cabinet 4. You should also label patch panels in a similar way so that 1-11-4 p7-2 would refer to the 2nd port of the 7th patch panel in cabinet 1-11-4. 4. Diagrams: Create diagrams that map the precise layout of servers in the racks and pre-install shelving and rack kits at the expected locations. It is a good idea to put the heavier equipment at locations near the bottom as this will make them easier to insert and remove. Make room for monitors and their KVM (Keyboard, video monitor, mouse) switches also. 5. Mobile Monitors: Video monitors on carts should also be available at the new facility for troubleshooting servers that need to be removed from racks or cabinets. 6. Rack Usage and Orientation: Install the servers in the same direction in the racks. This will make all power and network cabling connections reside neatly on one side of the racks. Servers on opposite sides of an aisle should either face each other or be back to back. This creates a better cooling environment as the hot power supply exhausts of one server won't be sucked in by the front facing air of the server behind it. CRAC units extract air through filters on the top of the unit and blow chilled air through vents at the bottom. It is for this reason that CRAC units should be placed in line with the hot aisles so that the air can easily be extracted from them. When regular flooring is used, you may require ducting to blow the chilled air into the cold aisle. With raised floors, the CRAC unit vents are physically below the floor level blowing air up into the server cabinets. In this case the baffles and sealed floor techniques mentioned in this chapter would help channel the air flow better. Sometimes with raised flooring, the air blown up through the cabinets is insufficient to cool the servers and perforated floor tiles need to be placed in the cold aisles for added cooling. Remember that perforated tiles located in hot aisles are counter productive as they will help to cool air the servers never use. As expected, the servers should be stacked vertically. When cabinets are used you should insert unperforated blanking panels in any spaces between the servers to better channel the cooling air from the front of the cabinet to the hot aisle in the back. Without the blanking panels, the usual swirling vortices of exhaust air can easily be blown back to the front of the rack through the spaces. Server cabinets come in a variety of widths, the most common one being 19 inches wide. Sometimes the walls between adjacent cabinets are removed to facilitate cabling. This can affect the correct channeling of the cooling airflow through the servers and can usually be avoided through better patch panel layouts ahead of moving time. Remember to make the aisles wide enough to allow people to easily mount and dismount servers in them. Finally, some types of equipment may be too heavy for regular server cabinets and will require the use of racks as an alternative source of support. This equipment will need to be identified and located accordingly. 7. Network Cabling: Determine your network cabling requirements based on your server layout. You may have to install patch panels to connect the server racks and cabinets to those containing your network equipment. You would then connect your server to a patch panel port in its rack with a standard network cable. This port is in turn connected to an equivalent port on a patch panel in the network rack. By using another standard length cable you can extend the connection to your network gear from the network rack patch panel. You may have to plan for the purchase and installation of such a system. Remember to consider the use of both copper and fiber connections. Copper Ethernet cable used for 100 Mbps communication can be no longer than 100m in length. Make sure that the

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combined length of your connections, via your patch panel system, does not exceed this length. Multimode fiber has a maximum distance of 2Km when running at 100 Mbps and between 220m and 500m when running at 1 Gbps. Glass fiber cables for servers are delicate in comparison to copper. Wherever possible ensure that they are run in separate cable trays to help prevent possible damage. Also make sure that the power cables run in separate trays or conduits from the data cables to reduce the risk of damage and electrical interference. To further reduce the risk of damage, cables shouldn't hang in the air or be stretched taught. Bundled data cables should be wrapped together with Velcro, and not plastic, tie wraps to make it easier to add additional wiring to the bunch. The bundles should be run to the sides of racks and cabinets so as not to impede airflow. 8. Tools: Make sure each person responsible for the racking of the servers has a correct set of tools. The most noticeable time saving tools will be electric screwdrivers. Have many and also have lots of charged replacement batteries. 9. Facility Access: Verify that each person that is going to have access to the server area has key access and parking rights at the data center beforehand. 10. Internet Connectivity: Ensure that your Internet connectivity to the area has been secured. Verify that the network links have been installed and tested prior to your migration date. Some sites require T1 data circuit links to credit card facilities or VPNs to remote offices. Make sure these are in place and tested before the move too. The entire relocation depends on the proper preparation of the server area but fortunately you can save time by simultaneously preparing for other aspects of the move. These will be explored next.

Network Preparation One of the most obvious reasons for having redundant network hardware is to help protect against hardware failure causing your Internet connectivity to fail. Another equally important reason is to help in server farm relocations. Redundancy allows you to shutdown network equipment, move it to the new location, and preconfigure it in anticipation of the server migrations. That isn't all, there are more preparations that need to be done. 1. Equipment List: As mentioned previously, do a complete inventory of all your networking equipment. Create a comprehensive list of all the important networking information that will change as a result of the move. 2. Diagrams: Ensure you have a complete set of network diagrams that include each server and network device that will be relocated. They should include every IP address, switch port, gateway, route, and ISP circuit number. Have separate drawings that clearly show how the network cables plug into the switches from each server. This will help illustrate whether too many of your servers are vulnerable to the failure of a single network device. Servers that play similar roles, such as database servers, should be directly connected to different switches. 3. Preconfigure: Setup your new network equipment at the target data center and test connectivity ahead of time. Connectivity should include tests from the Internet and practice servers at the new location. Make sure your routing, access control lists, VPN tunnels and firewall rules all take the IP addressing scheme you will be using at the new location into account. 4. Monitoring: Special attention should be given to network monitoring. Verify that you'll be able to switch monitoring from your old server address to the new one seamlessly. 5. Data Circuits: Keep close track on the provisioning of data circuits for the new location so that they are installed prior to the migration date. These circuits should not only be sized to capably


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handle your expected data transfer rates but also tested at various times of the day to ensure your ISP has met their contractual commitments. Some types of equipment require modem lines to provide emergency out of band technician access in the event of an emergency. This would require the additional installation of one or more POTS telephone lines. 6. Cabling: Make sure that network cables are all re-labeled to reduce the risk of human error when the servers are reconnected to their new network. 7. Logging: Many managed networks have centralized error logging and authentication servers. Make sure your relocated network devices can continue to do so. 8. Backups: Create copies of all your network configurations, both old and new prior to the relocation. The old ones will be helpful if you have to quickly roll back the work to the original data center. The new ones will help protect against hardware failure in your new facility. 9. VPNs: Some corporate offices use VPNs to gain access to their Web server farm. If possible, terminate some test VPN tunnels on the network equipment at the new location ahead of time. Once the migration is complete you'll have to plan for recreating a redundant network architecture in the new location. This will be covered in Chapter 3, "Post Relocation Activities".

Server Preparation Server preparation for the migration is probably the most complicated task because there are usually many of them with each running multiple applications that rely on the functioning of varying components. Follow these simple steps to make the job easier. 1. Server List: Do a complete inventory of all your servers. Create a comprehensive list of all important server information that will change as a result of the move. This can be recorded in a simple spreadsheet and would include IP addresses, subnet masks, routing gateways, backup server IP addresses, the switch ports the servers will use and server rack locations. It should also include information such as the server's name and serial number for inventory purposes. Each server should also have its own separate worksheet document that contains all its relocation information. This would be attached to the server so that the engineers working on it would be able to instantaneously reconfigure it when it arrives at the new location. Samples of both documents are available in Appendix I. 2. TCP/IP ports: It may seem tedious, but get a printout of all the TCP/IP ports on which the server is listening and also which clients have active connections to your server. This can be done with the netstat -a command in most operating systems, including Windows. This will help you to identify the applications that should be running before and after the relocation and can be used as a quick check to detect any unexpected failures. It will also be helpful in more precisely restricting the TCP/IP access between servers on your new networks. Finally, it will help to identify inter-network application dependencies between servers which can be used to determine the servers that should be relocated together as part of the same group. Most operating systems can also give you a snapshot of services or applications that should be running on startup. Get printouts of these for each server as part of the server's more comprehensive post migration system check. 3. Routing Tables: Note the routing tables of all servers before the migration using the netstat -nr command. Determine what the new routes should look like at the new location and note it down. This is especially important for noting the default gateways and also for analyzing routes on servers with either multiple NICs or routers. Note: A server should have only one default gateway. In Linux and UNIX systems there is only a single place to enter this value. Windows servers provide the option of having a default gateway per NIC. In this case, make sure that only one NIC has a default gateway configured. 4. Data Backups: Archive all your server data. Make sure that you have a data restoration unit at the remote location that will be able to restore your data from your backup media using the

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same software. The recent advent of portable external hard disks using USB 2.0 connections could simplify smaller backup and restoration work. Large databases are often stored on storage area network (SAN) and network attached storage (NAS) devices and are too large for the USB solution. In these cases data restoration by tape can be excessively long which can make this an option of last resort. With SAN and NAS data bases you may need to lease a duplicate device and clone your data to it. Disaster recovery can be much faster as the secondary device will be preconfigured to replace the failed primary one. Another option is to restore the data ahead of time on the new NAS / SAN equipment located at the new facility. You can then set up a data circuit between the old and new data centers so that any new transactions can be replicated between the two. At any moment in time the data bases at the two locations will be synchronized. Always remember to do practice data backups and restorations for key servers and applications. 5. RAID BIOS Settings: An often ignored item is the server's BIOS settings. The regular parameters are usually easy to determine as the defaults are usually sufficient. The real problem is with the BIOS metadata on hardware RAID cards. This metadata lists all the drives in each RAID set, the order in which they are accessed in the RAID set and the type of RAID being used. This often cannot be guessed. Schedule a server reboot before the relocation and enter the RAID controllers BIOS setup to record this information. Without this simple plan, a sudden jolt of a RAID card's loose onboard battery backup could cause you hours of downtime. 6. Spare Parts: If possible, have a set of spare servers that can be used for spare parts or complete system replacements in case of failure. 7. Customized Procedures: In many cases applications on servers have to be started or shutdown in a particular sequence. Sometimes co-dependent servers have to booted in a special order. You will need to document these special procedures wherever they exist and make note of them in your project plan. It may also influence the order in which the servers are relocated to the new data center. 8. Migration Timetable: Perform a careful audit can help to determine the number of days over which the migration should be spread and the sequence of the server moves. This will require you to account for each application within your environment which should also include their interdependencies with every other application, their software interfaces, the firewall rules that protect them and any application batch or cron jobs they rely on. The audit will also help to determine the groupings of systems that should move together. 9. Base Equipment List: Create a minimum list of servers that absolutely have to be up and running in order to maintain the web farm's functionality. It will help to focus the minds of the team members in the event of multiple failures. 10. Functionality Testing: Create a short list of tests for each server that will be used to verify that it is functioning correctly. Don't limit this to just network connectivity, but also check that all the required applications have started correctly and that some simple business operations can be successfully completed. 11. Application Code Surveys: Test to make sure your applications don't use IP addresses to access information on remote servers but use DNS names instead. The relocation may force you to change the IP addresses of devices and could cause some programs to fail unless this precaution has been taken. The general steps required to prepare your servers for the migration are not hard but the process can become difficult due to the sheer volume of information you need to track. Plan well and you should be able to have a successful project.


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DNS Preparation If the relocation requires the IP addresses of your site or servers to change then you'll have to make plans to adjust your DNS settings during the relocation. There are two things to remember with DNS. The first is that it will take at least 48 hours for any DNS change to propagate across the Internet. The second is that every DNS entry has an associated time to live (TTL) value which defines how long DNS caching servers should store the entry for local use before being required to query the entry's authoritative DNS server to see whether there have been any changes. With this in mind, here is what needs to be done: 1. Set The TTL: There is no magic bullet that will allow you to tell all the caching DNS servers in the world to simultaneously flush their caches of your zone file entries. Your best alternative is to request your existing service provider to set the TTL on your web site, for example www.myweb- site.org, in the DNS zone file to a very low value, say one minute. As the TTL is usually set to a number of days, it will take at least three to five days for all remote DNS servers to recognize the change. Once the propagation is complete, it will take only one minute to see the results of the final DNS configuration switch to your new server. If anything goes wrong, you can then revert to the old configuration, knowing it will rapidly recover within minutes rather than days. 2. Server Based Testing: Set up your test server in house. Edit the /etc/hosts file to make www.my-web-site.org refer to its own IP address, not that of the www.my-web-site.org site that is currently in production. This file is usually given a higher priority than DNS, therefore the test server wi ll begin to think that www.my-web-site.org is really hosted on itself. You may also want to add an entry for mail.my-web-site.org if the new Web server is going to also be your new mail server. Test your server based applications from the server itself. This should include mail, Web, and so on. 3. Client Based Testing: Test the server from a remote client. You can test the server running as www.my-web-site.org even though DNS hasn't been updated. Just edit your /etc/hosts file on your Web browsing Linux PC to make www.my-web-site.org map to the IP address of the new server. In the case of Windows, the file would be C:\WINDOWS\system32\drivers\etc\hosts. You may also want to add an entry for mail.my-web-site.org if the new Web server is going to also be your new mail server. Your client will usually refer to these files first before checking DNS, hence you can use them to predefine some DNS lookups at the local client level only. 4. Check All Domains: Make sure similar steps are taken for all your DNS domains. Remember to also update the DNS entries for your mail servers, they are generally located in a different section of the DNS zone file and can be easily overlooked. 5. Prepare to Switch: Once testing is completed, coordinate with your Web hosting provider to update your domain registration's DNS records for www.my-web-site.org to point to your new Web server at the time of the relocation. Plan to change your DNS TTL at least a week before the expected migration to limit it risking the success of your project. DNS management is probably the easiest task to accomplish but poor DNS planning can unexpectedly delay your project with your only recourse being to sit and wait for the changes to propagate.

Transportation Preparation A relocation would certainly not succeed without adequate transportation therefore it should be planned well. Here are some factors to consider.


26


1. Moving Company Selection: Get multiple quotations from movers, preferably with each provider giving a guaranteed maximum price for the job. Cost shouldn't be the only factor. Investigate the reputation, staff training, moving van cleanliness and safety, performance record, reliability, and the claims settlement customer service of each moving company. Visit the mover's office to verify they have a business. Determine whether the company belongs to a trade organization that requires a code of ethics and operation. Carefully consider whether the staff are people you want to do business with. 2. Reserve Transportation: If you choose to rent or use movers, have guarantees that the transportation will arrive on time. 3. Physical Protection: For large quantities of servers you'll need to have racks or shelving preinstalled to accommodate as many servers as possible. You should also ensure that the servers are securely fastened to prevent shifting in transit. Do not stack servers one on top of the other as this increases the risk of damage. Some of the more delicate devices may have to be specially wrapped for their protection in bubble wrap or foam. Some may have to be bolted to shipping pallets and mechanically moved. Finally, some vendors with full coverage maintenance contracts my stipulate that their staff be the only persons authorized to package the equipment. Make adequate preparations in advance. 4. Internal Logistics: Servers can be heavy. Get access to hand carts or wheeled dollies on which the servers can be manually pushed within the buildings. If practical, rent ramps to reduce the need to manually transfer servers at the various stages of transportation along the way. 5. Insurance: You may have to insure the equipment prior to the relocation. Check to make sure the selected moving company carries the required insurance coverage. If they break or lose something, you should request that it be fixed or replaced to the limits of their liability. There can be many clauses to this type of coverage, make sure the mover clearly explains the extent of your exposure. Transportation is often given the least amount of thought and servers will inevitably be carried on the back seat of cars. Avoid this as much as possible, renting a truck or using professional movers will be much faster, easier to track, less prone to equipment damage and easier to insure. You may be tempted to save money here, but the few dollars spent on ensuring proper transportation can save thousands in potential down time.

Conclusion The preparative tasks for a server farm relocation can be complex but with the right tools and planning it can be very manageable. Sample check lists, and post mortem forms are available in Appendix I. Chapter 3, "Post Relocation Activities" will begin by discussing what needs to be done during the relocation and will end with a number of activities that need to be completed once the project appears to be over. Most importantly, it specifically outlines what to do if things start to go wrong.

Chapter 3

Post Relocation Activities The deadline day has finally arrived. What should you do? It may not be as straightforward as it first appears. This chapter outlines some precautions you'll need to take.

Activities During the Relocation It may appear that with good planning the relocation should progress smoothly. That is largely true but the challenge is in the coordination of the activities when they go right and when they go wrong. 14. Customer Communications: Send out a notification to all affected parties that the migration is about to begin. Move the servers in the predefined order on your check list. 15. Team Allocations: You'll probably need to split your team into four groups. Those responsible for the shutdown of the old site, the physical movement of the servers, the booting up of the servers in the new location and testing. 16. DNS Updates: You'll have to synchronize the update of your DNS entry with the movement of the servers. Coordinate with your DNS provider to update your domain registration's DNS records for www.my-web-site.org to point to your new Web server. As the TTLs were set to one minute previously, you'll be able to see results of the migration within minutes. Once the migration is complete, you can set the TTL back to the original value to help reduce the volume of DNS query traffic hitting your DNS server. Delete any test entries in your server /etc/hosts files to make sure they don't unexpectedly interfere with future migrations. 17. Testing: The overall project manager should have a check list, white board or some other highly visible tracking system to monitor the basic status of every device being migrated. The testing teams should report the status of each device periodically. They should place one of three markers on each system. It may be something as simple as a sticky note, or self adhesive dots that are commonly available in office supply stores. These should include status colors for "untested", "successfully tested" and "failed" with only one color being assigned at a time. The red, green and yellow traffic light colors are one obvious choice. 18. Troubleshooting and Recovery: Things will go wrong. Make sure you have a conference call bridge open throughout the activity period. Try to limit the attendees to only managers once the initial problem has been identified as your technical staff will function best if left relatively undisturbed during troubleshooting. Assign a technical lead to be responsible for the full recovery of the situation even if the solution wanders outside of their area of expertise. The advantage of doing this is that it ensures that there is at least one technical person on the line who has a complete understanding of the history of the problem. This makes the transfer of troubleshooting responsibility from group to group much smoother. It is also a good practice to have an equivalent managerial lead for overall responsibility of the issue. If more than one problem occurs create another conference bridge and assign another pair of technical and managerial leads to reduce confusion. The use of email to track the minute by minute progress of a problem is generally counter productive as many of the participants will not have access to email during the activities. This can cause delays. Assign someone to issue general status messages when milestones in the troubleshooting have been reached. The abundant use of the "Reply All" button should be avoided as many team members will miss one of the many email threads. In times of crisis real time communication is always best, make sure everyone has access to a mobile phone.

28



If things are going really badly, and you have passed your point of no return, focus your resources on getting your minimum set of servers functioning as quickly as possible. If not, execute your roll back plan to return your servers to the original data center. 19. Monitoring: Verify that the monitoring and error logging are working correctly and that your predefined basic functionality testing is progressing as planned. You will need to execute more detailed testing later and this will be covered in sections to follow. Without good contingency planning the success of the project could quickly falter. The steps outlined previously should help to further guarantee that your preparations help to achieve your objectives.

Post Relocation Activities Relocation activities don't end with the passing of the deadline date. There are many other factors to consider. 1. Thorough Testing: Test to make sure your customers and partners can gain access to the expected areas of your server farm. Run through some predefined transactions to test the health of your applications in the new environment. 2. Relocate Redundant Equipment: In many migration plans, half of a redundant pair of devices is moved first as part of the main migration with the second device in the pair being moved at a later date. This can create unexpected problems, for example, the newly inserted equipment may overwrite the configuration of its partner with the configuration used at the old location. Plan for this eventuality by reading your equipment handbooks and having a copy of the valid configurations close at hand. The new equipment may also have to be configured for the IP address, logging, monitoring and authentication schemes used at the new facility. 3. Contract Negotiations: Contracts relating to the old server facility will have to be terminated or reapplied to the new location. This would include maintenance contracts, contractor services, leases and data circuits. 4. Service Level Verification: Verify that all the promises made by the management of the new facility have been met. Measure temperatures, test maximum data throughput rates, do practice data backups and restorations, confirm the use of redundant power feeds, make sure the information in your online customer care portal is correct, and test the facility's response time to do standard changes. 5. Redundancy Testing: Plan to test the redundancy of the site. This may be as simple as disconnecting one of your Internet links and seeing whether traffic reaches your site through an alternative ISP. It could also be more complicated such as doing a database cluster failover or network device reboot. It's never a good thing to merely assume that your architecture is redundant. 6. Monitoring and Reporting: Verify that your logging and monitoring are working correctly. Simulate some known but non fatal errors and see whether your systems can detect them correctly. 7. Documentation: Modified environments usually require updated documentation. Diagrams and procedures are often tedious to change but the time spent confirming the accuracy of your information can greatly improve the efficiency of your operations staff and make troubleshooting much quicker. 8. Examine Architecture Changes: It is generally not a good idea to incorporate major changes in the network architecture of your server farm as part of the relocation. It will tend to increase the complexity of the tasks and the likelihood of failure. A project to re-architect your farm after the relocation is much more desirable. There is one type of simultaneous re-architecture that can gain many rewards with relatively small risk. Older server farms tend to have all servers directly connected to pairs of high capacity switches located in a central location. This can make cabling costs high. A simple alternative is to maintain your investment in these central switches, but have them connect to smaller "pizza box" sized switches in each rack or cabinet. Servers can then be connected to the switch in their rack


29

and the switch can then aggregate, or "trunk", the required networks/VLANs to the main central switches. Very little routing changes are required in this architecture. The cabling becomes much cheaper and less complicated, the addition of a new rack only requires one or two cable runs to the central switches and short standard length cables connect the server to their local switch. Expansion can be done using cheaper commodity switches instead of more expensive blades that need to be fitted into the central departmental switches. There is the risk of having increased points of failure, but the failure of one of these small switches is less likely to threaten your entire site and if they do fail, the replacement cost and time is usually less. There is also the complexity of managing additional switches but the use of automated network device backup software such as RANCID can significantly reduce some aspects of administration. Another risk is that backup traffic on one network can choke out Web traffic traveling on the same trunk, in departmental switches the backplane or master bus can usually handle this type of situation easily. You can largely avoid this problem by using Gigabit instead of 100 megabit per second fast Ethernet trunk uplinks. In extreme cases you may have to consider using separate switches for Internet facing and internal networks/VLANs. This solution may not be suitable for your existing environment, but it may be worth investigating for newer projects. Remember that in this architecture the firewalls, load balancers and all other networking equipment except the rack based switches should be directly connected to the departmental switches. This prevents data from bouncing around from rack to rack as it passes from firewalls, to load balancers and then to servers. If this is not done, a single saturated trunk to one of the racks could take your entire site offline instead of only a small group of servers. With Gigabit links this is usually an unlikely scenario, but prevention is always better than the cure. 9. Rental Returns: Remember to return all items rented as part of the migration. This would include moving trucks, dollies, trolleys and shelving. 10. Infrastructure Checks: Verify the ambient temperature and humidity in the aisles meet the specifications of the CRAC unit vendor. Also check that the temperature at the front and rear of each server conform to the requirements of the manufacturer. 11. Documentation Storage: Store all documentation related to the project in electronic form in one location so that it cal be reused and accessible by all. 12. Security Audits: Now that the relocation is complete you should perform a complete security audit which should include a remote network vulnerability scan; verification that all installed software is authorized, correctly patched, and regularly scanned for viruses if applicable; confirmation that only authorized persons have physical and network access to your systems; and checks to see whether firewall rules need to be adjusted to match the new needs of the organization. 13. Project Audit: You should conduct a post-move audit and review of the data center relocation project. This should compare the results to the initial business case, conformity to schedule and cost estimates and feedback from team members and key stakeholders. The lessons learned from the data center move/relocation project can be used to enhance future projects. The audit will also highlight areas of day to day processes that will need attention and so it should be used as a means of improving the universal strategic goals of improved simplicity, lower cost and increased speed. 14. Party Time! When it's all over have some form of recognition of the hard work done by all your staff. Incentives such as extra time off, commendations for people who genuinely saved the day, an outdoor barbeque, a pot-luck, a fun day, cinema tickets for the whole office to see the latest blockbuster movie, or a small party can all be arranged at little extra cost. They should have an element of surprise and most importantly should be held outside of the office, for example on the lawn, in a nearby park or at a restaurant. Special events aren't usually viewed as being special if they are held in the usual everyday surroundings. If the migration required weeks of late nights in preparation and execution, and there is a sufficient budget allocation, invitations to the event should be extended to the immediate families of your staff. They had to bear the absence of loved ones working under stress over extended periods of time. Without their inclusion the project would only be an economic victory not a morale building exercise. It is important to recognize the talents and new skills learned by the members of the


30


company and the tolerance of their families. These are a few of the activities that need to be executed after the dust has settled but they are no less important than any other task. The relocation is only finished once there is complete peace of mind.

Conclusion Server relocations can be daunting projects but the tools and knowledge provided in this book should allow you to ably complete the project with few unexpected complications. Remember that, as with any project, careful planning is critical to success and should be taken seriously by everyone involved.

Appendix I

Relocation Check This appendix has samples of all the various forms you may need as part of the relocation. They cover all the preparation, execution and cleanup tasks mentioned in earlier chapters.


32


Data Center Rating Form In this table, give each item a weight (W) from 1 to 10 depending on how important it is to you. When visiting the data center give each item a score (S) from 1 to 10. At the end of the visit multiply W and S to get a sub total. The data center with the highest grand total will be the most desirable. Note: Data center ISP related factors are covered in the ISP rating form Data Center Name:

________________________

Engineer: ___________________

Date:

________________________

Contact: ___________________

Score (S) Sub- Total (W x S) Item

Description

1.

External flood risk

2.

Proximity to highways. Greater than 250 meters

3.

Proximity to railways. Greater than 250 meters

4.

Proximity to hazardous production facilities

5.

Proximity to reasonably priced housing

6.

Proximity to good schools

7.

Proximity to recreational areas

8.

Connectivity to public transportation

9.

Proximity to airport flight paths

10.

Grounds susceptible to localized flooding

11.

Embankments and security fencing surrounding the building

12.

Availability of roof access rights.

13.

Power feeds from multiple substations

14.

Building has sufficient excess power capacity for growth

15.

Adequate UPS coverage for expected load

16.

Staff automatically alerted when poor power line conditioning is detected.

17.

UPS N+1 redundancy. Sufficient extra

Comments

Item Weight (W)

Score (S)

SubTotal (W x S)


Item

Description

units to allow for offline maintenance without jeopardizing coverage.

18.

Standby generator N+1 redundancy. Sufficient extra units to allow for offline maintenance without jeopardizing coverage.

19.

Redundant PDUs supply your desired floor space.

20.

Redundant PDUs are less than 50% loaded.

21.

Facility can support the power per square foot required by all our equipment.

22.

Facility has sufficient power to support server load expansion into the foreseeable future.

23.

Each rack or cabinet is fed by both PDU units.

24.

Standby generators are regularly tested under load

25.

UPSs are regularly tested

26.

Air temperature at 75F / 25C

27.

Signs of leakage or rattling from the CRAC units.

28.

Offices and common areas isolated for data center floor.

29.

Mandatory visitor registration or electronic ID access.

30.

Biometric access to data center.

31.

Smoke and heat detectors.

32.

Pre-action fire suppression system.

33.

Liquid detectors under the raised floor tiles.

34.

Graphical fire alarm panel with map of data center floor.

35.

Job tickets automatically created when facility's equipment fails.

36.

Lead times for change requests meet your minimum response times.

37.

Availability of web based customer

33

Comments

Item Weight (W)

Score (S)

SubTotal (W x S)


34

Item

Description

care portal.

38.

Problem escalation procedures meet your needs.

39.

Availability of 24/7 remote hands access.

40.

Power and cooling costs

41.

Floor space costs

42.

Monitoring costs

43.

Automatic data backup services provided

44.

Backup media compatible with existing systems at current data center.

45.

Backup media with valid data is stored off site

46.

Backup media is reused after an acceptable period in off site storage.

47.

Technicians on site to provide "remote hands" access to servers.

48.

Antistatic tiles used on floor

49.

Water pipes, steam pipes, kitchens and bathrooms located away from the computer area.

50.

Facility allows you to reserve neighboring space for future expansion.

51.

Data center area of the facility protected by fire proof doors.

52.

Site has 24/7 video surveillance

53.

Site has biometric or some other form of keyless entry system to gain access to the server area.

54.

Facility allows all your required types of data circuits

55.

Facility allows access to all your required ISPs and data circuit carriers.

56.

Facility provides access to multiple desired ISPs or data services carriers.

57.

ISPs and carriers at facility have sufficient capacity to meet your future

Comments


Item Weight (W)

Score (S)

SubTotal (W x S)


Item

Description

needs for each type of circuit.

58.

Facility has multiple ISP / carrier local loop options. (Reduce single point of failure or pricing negotiation risk)

59.

Facility local loops use diverse paths into facility. (Reduce single point of failure risk)

60.

Facility's CFA process meets timing, procedural needs.

61.

The provisioning of data circuit cross connects meets timing, procedural and cost requirements. Grand Total

35

Comments

Item Weight (W)

Score (S)

SubTotal (W x S)


36


ISP Rating Form In this table, give each item a weight (W) from 1 to 10 depending on how important it is to you. When visiting the data center give each item a score (S) from 1 to 5 At the end of the visit multiply W and S to get a sub total. The data center with the highest grand total will be the most desirable. Data Center Name:

________________________

Date:

________________________

Item

Description

1.

5 minute or better network monitoring polling cycle

2.

Number of failed polling cycles that trigger alarms (Usually 3)

3.

Job tickets automatically created when polling fails?

4.

SNMP based network monitoring.

5.

Use of SNMP traps to generate job tickets automatically.

6.

Multiple DNS servers in multiple geographic locations.

7.

Adequate lead times for DNS change requests.

8.

Lead times for regular change requests meet your minimum response times.

9.

Availability of web based customer care portal.

10.

Problem escalation procedures meet your needs.

11.

Bandwidth costs (Local Loop)

12.

Bandwidth costs (95th percentile)

13.

Lead time for provisioning data circuit.

14.

CIR acceptable

15.

CIR can be incremented to meet your projected needs

16.

Signs of congestion on network that would prevent the ISP form meeting the contractual CIR

Comments

Engineer: ___________________

Contact: ___________________ Item Weight (W)

Score (S)

SubTotal (W x S)


Item

Description

17.

SLA guaranteed uptime (Percent)

18.

Scheduled maintenance windows meet your timetable needs.

19.

Scheduled maintenance windows give adequate advance notification.

20.

Are NOC staff certified in the equipment they monitor?

21.

NOC escalation procedures meet your needs.

22.

Type of data circuit to be provided. (T1, E1, DS3, OC3, HSSI, Ethernet, HSSI, etc.)

23.

Does ISP have out of band access (eg. Modem connection) to gain access to their equipment if their data circuit fails.

24.

How often are error rates monitored to trigger maintenance?

25.

At what error rate triggers mandatory maintenance?

26.

What is your procedure for scheduling technician visits to fix line degradation problems?

27.

Do you provide full BGP routes?

28.

We have our own BGP AS number with our own networks. Will you be able to advertise these to the Internet if we peer with you?

29.

Do you have fully redundant paths to each of your BGP peering transit providers and the router to which we will be peering?

30.

We may need to adjust BGP routing to amount of bandwidth we push through your circuits. Do you support AS path prepending?

31.

Is your networking infrastructure fully protected with UPS and standby generator power?

32.

Who do you peer with for Internet transit?

33.

Facility allows all your required types of data circuits for this ISP

34.

Facility allows access to this ISP / data circuit carriers.

Comments

37

Item Weight (W)

Score (S)

SubTotal (W x S)


38

Item

Description

35.

ISP / data circuit carrier has sufficient capacity at facility to meet your future needs for each type of circuit. Grand Total

Comments


Item Weight (W)

Score (S)

SubTotal (W x S)


39

Cost Justification Work Sheet Calculate the expected monthly change in profit and expenses over the expected life of the servers in the new data center and off set this against the expected startup capital outlay costs to determine the economic merit of the relocation/consolidation project.

Potential Monthly Profit Improvement Done By: ________________________

Item

Description

1.

Expected increase in profits due to increased sales facilitated by improved data center activities.

2.

Eliminated risk to profits by moving to a more suitable data center. (Less revenue loss due to infrastructure being incapable of supporting customer needs, or systems outages)

3.

Liberated cash flow due to consolidated operations

Grand Total

Comments

Date: ___________________

Old Facility

New Facility

Net Change


40


Relocation versus Data Center Upgrade Capital Outlays Done By: ________________________

Item

Description

1.

Leasehold improvements cost

2.

Transportation moving costs

3.

Overtime expenses

4.

Increased staff hiring expenses

5.

Contractor fees

6.

Training fees

7.

Equipment acquisition

8.

Temporary leases for the relocation or upgrade

9.

Cleanup costs

10.

Penalty fees

11.

Staff layoff expenses SUB Grand Total

Comments

Date: ___________________

Old Facility

New Facility

Net Change


41

Monthly Costs Done By: ________________________

Item

Description

1.

Air conditioning lease

2.

Air conditioning maintenance

3.

Data backup equipment leases

4.

Data backup services

5.

DBA services

6.

Fire systems maintenance

7.

Floor space lease

8.

ISP fees

9.

Janitorial services

10.

Network equipment leases

11.

Network management services

12.

Power

13.

Data backup replacement media expenses

14.

Security services fees

15.

Security systems maintenance

16.

Server leases

17.

Server maintenance contracts

18.

Server systems administration services

19.

Software licenses

20.

Software maintenance contracts

21.

Staffing expenses

22.

Standby generator lease

23.

Standby generator maintenance

Comments

Date: ___________________

Old Facility

New Facility

Net Change


42

Item

Description

24.

Systems development expense

25.

UPS maintenance fees

26.

Web site monitoring expenses

27.

Staff expense

Comments

Grand Total Net Change Description Old Facility New Facility Net Change


Old Facility

New Facility

Net Change


43

Coordination Preparation Check Sheet Done By: ________________________

Item

Description

1.

Project manager assigned

2.

Networking team lead identified

3.

Transportation team lead identified

4.

Server area team lead identified

5.

Server team lead identified

6.

Customer communication lead identified.

7.

Catered food lead identified (Pizza, Veggie, Kosher, Halal, etc.)

8.

Post mortem team created to analyze any failures in the process.

9.

Gofer identified

10.

Disaster recovery team lead identified

11.

All members of the relocation team will have functioning mobile phones on the day or the migration.

12.

Conference call bride arranged

13.

Best time and date for relocation identified

14.

Team aware of method to be used to identify malfunctioning equipment.

15.

Short list of scenarios during which the relocation will have to be rolled back has been created.

16.

Point of no return identified.

17.

Minimum list of functional servers for successful migration created.

18.

Sequence list of which equipment will be moved, and when, created.

19.

Roll back plan created that includes the sequence in which equipment will be returned.

20.

Server list / inventory spreadsheet has been created and distributed to all teams.

21.

Application audit performed for all servers to account for interdependencies with other applications.

Date: ___________________

Priority

Person Responsible

Deadline

Status


44

Item

Description

22.

Procedures documentation completed for each server / network device

23.

Equipment that will have to be leased or purchased to facilitate the relocation has been obtained

Priority


Person Responsible

Deadline

Status


45

Customer Communication Check Sheet Done By: ________________________

Item

Description

1.

Single message of varying degrees of detail created for each customer group.

2.

Internal customers alerted of plan

3.

External customers alerted of plan

4.

Draft notifications to be used in the event of failure and success created.

5.

Short list of customers to be kept updated by phone created.

6.

Post mortem template identified

Date: ___________________

Priority

Person Responsible

Deadline

Status


46


Server Area Preparation Check Sheet Done By: ________________________

Item

Description

1.

Racks and cabinets installed in new location.

2.

Adequate power supplied to each rack and cabinet

3.

Each PDU in the server area can handle the failure of the other redundant one supplying the area.

4.

Adequate cooling provided for expected server heat load.

5.

Power outlets are labeled to indicate the PDU that supplies them.

6.

Verify that you have power cables in sufficient quantities and adequate lengths.

7.

Power cables are labeled at both ends.

8.

Power supplied is of the correct voltage using the desired connectors.

9.

Servers in racks and cabinets won't overload the power circuits that supply them.

10.

Diagrams created to show the server layout in the racks or cabinets.

11.

Shelving and rack kits for servers pre installed in cabinets and racks.

12.

KVM (Keyboard, Video Monitor, Mouse) switches preinstalled.

13.

Rack mounted keyboards and monitors installed in cabinets or racks.

14.

Racks and cabinets clearly indicate the server orientation to create hot and cold aisles.

15.

Keys given to all persons who require access to the server area.

16.

Staff doing the server "Rack and Stack" work have adequate tools especially electric screwdrivers.

17.

Data circuits for internet connectivity have been run to the racks to be used by the networking equipment.

18.

Monitors on carts available for troubleshooting servers that need to be removed from racks.

19.

Antistatic tiles installed on floor

Date: ___________________

Priority

Person Responsible

Deadline

Status


Item

Description

20.

Water pipes, steam pipes, kitchens and bathrooms located away from the computer area.

21.

Patch panels installed correctly

22.

Patch panels have the correct connectors.

23.

Cable lengths through the patch panels are under 100m in length.

24.

Glass fiber and copper cables run in separate cable trays.

25.

Server area is large enough to accommodate future expansion.

26.

Aisles between racks wide enough to allow people to easily mount and dismount servers in them.

27.

Server area has 24/7 video surveillance

28.

Server area has biometric or some other form of keyless entry system access system.

29.

Copper data cables, fiber data cables and power cables run in separate conduits or trays.

30.

Data cables not hanging in the air or pulled taught.

31.

Patch panel cable bundles run to the sides of racks and cabinets so as not to impede airflow.

32.

Adjacent server cabinets do not have their walls removed.

33.

Few air flow obstacles under the raised floor area.

34.

Baffles used under the raised floor area to improve airflow.

35.

Raised floor under the cooling zone of each CRAC unit is sealed to force air through desired cabinets.

36.

Perforated floor tiles only used in cold aisles.

47

Priority

Person Responsible

Deadline

Status


48


Network Preparation Check Sheet Done By: ________________________

Item

Description

1.

Network equipment with dual power supplies are plugged into electrical circuits from each PDU.

2.

Groups of servers with similar function (eg. DB servers) are connected to redundant switches in a 50/50 fashion.

3.

Each server is labeled on the front and back.

4.

Data circuits to be used by the network gear have been tested.

5.

Sample configurations have been created for all networking devices with the new network addresses to be used at the new location.

6.

The standby devices in redundant pairs of networking equipment at the old location have been shutdown, shipped to the new location and preconfigured.

7.

Complete network diagrams of the new location have been created.

8.

Test VPNs to remote offices have been created.

9.

Network devices are labeled in the front and back.

10.

All network cables labeled at both ends.

11.

POTS lines installed for out of band access.

12.


13.

Data circuit capacity requirements identified for both production Web access and possible data replication between data centers.

Date: ___________________

Priority

Person Responsible

Deadline

Status


49

Server Preparation Check Sheet Done By: ________________________

Item

Description

1.

Servers with dual power supplies are plugged into electrical circuits from each PDU.

2.

Groups of servers with similar function (eg. DB servers) with single power supplies are connected to redundant PDUs in a 50/50 fashion.

3.

All server power cords labeled at both ends.

4.

Each server's "netstat -an" output has been recorded.

5.

Each server's "netstat -nr" output has been recorded with the expected output at the remote location prepared.

6.

Server data backed up.

7.

Practice data backups and restorations done for key servers and applications.

8.

All RAID BIOS settings recorded.available (replication scenario)

9.

Spare servers identified as possible sources of spare parts or as "hot standby" devices.

10.

Sequence of servers to be moved identified.

11.

Sequence of how the servers will be returned moved in the event of a roll back identified.

12.

Testing short list created for each server.

13.

Applications vetted to make sure they refer only to DNS names not IP addresses.

14.

Minimum list of servers for correct site functionality created.

15.

Special operating procedures for key servers created. (eg. Documentation of the sequence in which servers should be booted or applications started)

16.

Snapshots of the actively running services or applications for each server has been created.

17.


18.

Amount of data to be backed up per server has been determined.

19.

Equivalent amount of production data storage

Date: ___________________

Priority

Person Responsible

Deadline

Status


50


DNS Preparation Check Sheet Done By: ________________________

Item

Description

1.

TTL on old DNS zone files set to 5 minutes and propagated to the Internet.

2.

New DNS zone files created with new IP addresses. (TTLs should remain at 5 minutes)

3.

Testing of application using new DNS entries in the test server's hosts file completed.

4.

Testing of website using new DNS entries in the web browser client PC's hosts file completed.

Date: ___________________

Priority

Person Responsible

Deadline

Status

Transportation Preparation Check Sheet Done By: ________________________

Item

Description

1.

Moving truck rented / Professional movers hired

2.

Mover has adequate insurance coverage

3.

Adequate method for stacking and securing servers in the truck found.

4.

Equipment insurance up to date.

5.

Dollies and carts available at both locations for moving the servers across the floor.

6.

Boxes purchased or rented for moving equipment and miscellaneous items.

7.

Special packaging for the more delicate items.

8.

Items under maintenance contract prepared for transportation by the equipment vendor, not internally.

Date: ___________________

Priority

Person Responsible

Deadline

Status


51

Activities During the Relocation Check Sheet Done By: ________________________

Item

Description

1.

Notifications sent to all customers that the activity is about to start.

2.

DNS using the new zone files has been propagated to the Internet.

3.

Emergency conference call bridge has been created for communication with team.

Date: ___________________

Priority

Person Responsible

Deadline

Status


52


Post Relocation Check Sheet Done By: ________________________

Item

Description

1.

All power cables labeled at both ends

2.

All network cables labeled at both ends

3.

Moving truck, dollies, carts, boxes and other transportation related items returned.

4.

New diagrams and other documentation created for adequate description of the new server environment.

5.

Error logging and monitoring occurring correctly.

6.

Contracts related to old facility terminated or re-negotiated for the new facility.

7.

All equipment at the new location has been restored to fully redundant operation.

8.

Redundancy testing of new server environment completed.

9.

Testing of data throughput rates at new location completed.

10.

Customers and partners can get adequate access to the servers at the new location.

11.

Test data backups of servers successful.

12.

DNS TTLs on new zone files have been reverted to a couple days.

13.

Security audits planned and executed.

14.

Blanking panels inserted between servers

15.

Server cable bundles run to the sides of racks and cabinets so as not to impede airflow.

16.

Ambient air temperature within design of the CRAC unit

17.

Ambient air humidity within design of the CRAC unit

18.

Intake temperature at the front of servers in the rack is within specification.

19.

Exhaust temperature at the front of servers in the rack is within specification.

Date: ___________________

Priority

Person Responsible

Deadline

Status


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Individual Server Worksheet Server Name:

Backup Done:

Make:

Model:

Serial Number:

Inventory No.:

Operating System:

Backup Done:

Engineer:

Date:

Old Data Center Item

Description

1.

Default gateway

2.

Server rack location

3.

NIC #1 IP address

4.

NIC #1 Subnet Mask

5.

NIC #1 Connected to switch named:

6.

Backup server IP address

7.

DNS server #1 IP address

8.

DNS server #2 IP address

9.

NIC #1 Connected to switch port number:

10.

NIC #1 Connected to VLAN number:

11.

NIC #2 IP address

12.

NIC #2 Subnet Mask

13.

NIC #2 Connected to switch named:

14.

NIC #2 Connected to switch port number:

15.

NIC #2 Connected to VLAN number:

16.

Attached Devices

New Data Center


54


Individual Server Worksheet (Part II) Additional Server Routes Item

Network

Subnet Mask

Gateway

1. 2. 3. 4.

Network Enabled Applications List (netstat -a output) (Will be same as that expected in New Data Center) Old Data Center

Old Data Center


55

Contractor Qualification Check Sheet Done By: ________________________

Item

Description

1.

Contractor has sufficient experience in the industry.

2.

Contractor has sufficient certified staff.

3.

Contractor has provided evidence of staff certification

4.

Contractor has the correct installation and testing tools

5.

Contractor lists the type and manufacturer of all testing tools

6.

Contractor is willing to guarantee the quality of their work in writing and back it with a one year warranty.

7.

Contractor has provided proof of doing similar work previously.

8.

Contractor has tested their work to your satisfaction and provided a test plan as proof.

Date: ___________________

Yes

No


56


Data Circuit Check Sheet Done By: ________________________

Carrier

Circuit Type

Qwest

T1 PRI DS3 GigE

Sprint

T1 PRI DS3 GigE

ATT

T1 PRI DS3 GigE

Verizon

T1 PRI DS3 GigE

Level3

T1 PRI DS3 GigE

etc.

T1 PRI DS3 GigE

etc.

T1 PRI DS3 GigE

etc.

T1 PRI DS3 GigE

Intermediate Carrier

POP Address

Date: ___________________

Vendor / Purchasing Check Sheet Done By: ________________________

Item

1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16.

Shipment Group

Product

Order Quantity

Date: ___________________

Shipped Quantity

Status

Scheduled Shipped Date

Date Shipped

Shipment Method

Data Center Ticket Number

Tracking Number

Number of Pieces

Post Mortem Analysis Sample Form Customer Information Customer Name

List all affected customers

Location

Data Center where incident occurred.

Date

Report Date

Author

Engineer working issue

Ticket Number(s)

Related work order or trouble ticket numbers

Incident Date

Date incident occurred

Post Mortem #

Assigned by the IR Administrator

Responsible Support Team

Engineer’s Department

Incident Summary A brief, factual description of the issue: Example: We received an alert from the monitoring system for customer X indicating sites were unavailable. The troubleshooting process indicated that the primary local-director (load balancer) had failed over to the secondary. There were also traps that indicated VLAN state changes on the Internet facing VLAN of the load-balancer. However, even after the load-balancer failed over to the secondary, the sites were still not accessible

Incident Detail Details from the ticket with time stamps (include event start time, escalation times & end time when customer confirmed resolution). Ensure all parties involved in the troubleshooting, escalation or communication are referenced, but do not use the individual’s names Example: Eastern Standard Time: Date: xx/xx/2004 05:24pm 05:29pm 05:30pm 05:34pm 07:24pm

– Event noted – Project Manager paged, site down – Escalated to Networking – Networking troubleshooting event – Confirmed with Customer site up

Customer Impact Duration of time the customer was impacted and aspect of the site that was not available. Example: Customer sites were inaccessible for 2hrs, from 5:24 pm to 7:24 pm.


59

Root Cause Analysis Underlying factor causing the incident. Ensure complex technical terms and company specific terminology is defined for the customer. Example: The local-director load balancer has etherchannel setup on its interfaces. The fail over load-balancer had its interfaces plugged into switch ports, which were not setup for ether-channel and were in the wrong VLAN. When the device failed over to the secondary device, it came active but was unable to pass traffic. When the primary device was made active, the sites were accessible

Corrective Action Plan Corrective actions taken to immediately address the issue and any planned actions to prevent reoccurrences and estimated completion dates of planned actions.

Example: o

Interfaces of the local-director were connected to the correct switch ports that had ether channel setup.

o

Tested Fail over and the status on the local-directors show no errors.

o

Will run an audit of the Customers net work diagrams to confirm correct setup.

o

Customer care representative will schedule a meeting to review site specs with customer in 2 weeks.

Appendix II

How to Choose a Data Center ISP In Chapter 2, "Preparing for Server Relocation", I outlined the importance of ISP preparation. This chapter will discuss the many technical factors that govern the selection process in detail. These factors include: 1. Pricing 2. Determining the type of data circuit to use. 3. Deciding on whether to use IP addresses issued by your ISP or addresses owned by your company. 4. Configuring a routing protocol to use with your ISP. Check lists are also included in Appendix I to help you make a better decision and facilitate your monitoring of the status of all the required tasks. First let's discuss these factors in more detail.

Data Circuit Pricing Pricing varies depending on the type of service you purchase. Internet circuits typically require you to commit to a minimum data rate and charge a variable fee for usage above that rate to a defined maximum. Non-Internet dedicated point to point services from data carriers usually charge a fixed fee that allows transfers up to the maximum data rate. There is no variable component. This will be discussed in more detail next.

Internet Services A very common ISP billing technique used is called the 95th percentile method. Here the internet service provider provides an absolute maximum data rate, also known as a committed information rate (CIR), but you are billed based on actual usage. The ISP samples your data rate every five minutes and sorts all the sample readings for the month from high to low. They then discard the top 5% of the samples with the highest utilization. You are then billed at the rate of the highest sample that remains, not the average of those remaining. One of the advantages of this billing method is that it allows you to download files, a usually bandwidth intensive process, for up to about an hour a day without it affecting your bill. In addition to bandwidth, you may also be charged a local loop rate which amounts to a monthly fee that covers your connection from your facility to the nearest telephone / Internet exchange. This is frequently proportional to the distance between the exchange and your facility. Sometimes this fee is also related to your CIR and you may find that you can reduce this monthly fixed cost my negotiating a lower CIR. You may also be able to reduce your 95th percentile rate by committing to a longer contract or by convincing your ISP that you will be generating sufficient traffic to justify a bulk discount.


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Non-Internet (Carrier) Services Data carriers typically will charge a flat fee for circuits with a pre-defined maximum data rate. You will also be charged a local loop rate. The complexities of a CIR and 95th percentile are usually absent.

Data Circuit Types The selection of the type of data circuit to be used will depend upon the amount of bandwidth you expect to use, the equipment available to your ISP in the area and the capabilities of your networking equipment. The most commonly used data circuit technologies include those listed in Table A3.1.

Table A3.1 - Common Data Circuit Terminologies Term

Description

T1

1.544 Mbps link that can be split into up to 24 x 64 Kbps channels. Channels can be aggregated together to increase throughput up to the T1 maximum in a configuration called a "fractional T1". Channels may be used for voice or data. Typically runs over copper

E1

2.048 Mbps link that can be split into up to 32 x 64 Kbps channels. Two channels are used for signaling. Channels can be aggregated together to increase throughput up to the E1 maximum in a configuration called a "fractional E1". Channels may be used for voice or data. Typically runs over copper.

T3

Circuit configured to carry DS3 formatted data at up to 44.736 Mbps. A DS3 can be fractionalized with up to 30 T1 circuits. Two circuits are used for signaling. This means a T3 can up to 672 x 64 Kbps voice/data channels. Typically runs over copper.

DS3

See T3

HSSI

High Speed Serial Interface capable of supporting up to 52 Mbps.

Packet Over SONET (POS)

Methodology carrying TCP/IP traffic over SONET networks. The TCP/IP packets are inserted into ATM packets which are then placed on the SONET circuit. You will most likely need a POS interface on your router if you intend to transmit TCP/IP, Voice over IP (VoIP ) or Internet packets on an OC type circuit. ATM interfaces may look the same, but are designed to strictly carry traditional voice traffic. Typically runs over fiber optics.

SONET Synchronous Optical Network.

International standard for transmitting digitized voice over optical fiber circuits. There are a number of SONET circuit types, the most commonly used ones being optical carrier levels 3 and 12 mentioned in this table. (OC-3, OC-12). Data traveling on SONET networks use asynchronous transfer mode (ATM) formatted packets which were originally designed to carry voice traffic. Typically runs over fiber optics.

Fast Ethernet

Primarily copper based version of Ethernet that operates at 100 Mbps.

Gigabit Ethernet (Fiber)

Optical version of Ethernet that operates at 1 Gbps.

Gigabit Ethernet (Copper)

Copper based version of Ethernet that operates at 1 Gbps. Term Description


62


Term

Description

Wireless Circuits

Uses a variety of methods to transmit data through the air. In most cases the ISP manages the antenna equipment and hands off a physical cable link to their customer. This link may be of any of the circuit types mentioned in this table. Wireless links can be quickly installed but they tend to be subject to interference that can reduce their reliability.

DSL

An adequate solution for low volume web sites. Usually offers a maximum bandwidth of 2 Mbps.

Cable Modem

Unsuitable for high bandwidth websites as your circuit is shared by many other subscribers who could affect your performance. Your bandwidth usage could also affect video quality of other subscribers. Some ISPs purposely restrict traffic to web servers on their cable links for this reason

It is good to note that data services are sometimes asymmetrical in nature, especially with DSL and cable modem circuits. This means that the incoming downstream data rate from the Internet is different from the reverse outgoing upstream speed. You should be most concerned about the upstream speed for your Web site to the Internet. Inbound Web browser queries don't use a lot of data bandwidth, but the Web pages that contain the outbound replies do. Internet service providers provide asymmetric services for residential users and the downstream rate is almost always higher than the upstream. They reserve symmetrical data circuits for businesses which usually need high bandwidth to both surf the web and serve Web pages and more reliable guaranteed service. The ISP will usually provide the business with a fixed range of Internet addresses as part of the service; residential customers usually get a dynamic address allocation which is unsuitable for most businesses. Whenever possible always opt for symmetrical services for your business. Remember that there are many ways to plan the expansion of your data circuit bandwidth. You can: 1. Add more circuits. 2. Order a high speed circuit and throttle it with a lower valued CIR. Increasing the CIR increases your bandwidth. 3. Use a factional or channelized service and expand your usage one channel at a time till the maximum capacity of the circuit is reached. Select your data circuit with care. A wrong decision could inhibit the growth of your business.

Data Circuit Provisioning You should always be aware of the environment in which data circuit providers work. In most cases neighborhoods are grouped into geographic zones which receive data communication services from a central office (CO). COs can also be called telephone or Internet exchanges. Usually the CO is owned and operated by a single incumbent carrier (eg. AT&T) that owns the wiring infrastructure all the way to the neighborhoods' homes and businesses. Competing carrier can sometimes arrange with the incumbent to provide competing services over the wired infrastructure for a fee. The connection between a CO and your business or home is often called the local loop. Ideally, a dedicated point to point data circuit between two neighborhoods should have a local loop in neighborhood "A", which then connects to the carrier's backbone network. The backbone should then provide services to the CO in neighborhood "B", which connects to the remote business via another local loop. For Internet services, there need only be a single local loop to your ISPs Internet infrastructure. Not all ISPs are present in all COs. In order to provide services to all neighborhoods in a city, ISPs may have to negotiate interconnections between COs. Therefore it is possible to purchase services from an ISP who then has to negotiate multiple local loops for the circuit to finally reach its backbone infrastructure.


63

It is best to minimize the number of local loops in your circuit design. Coordinating the installation and troubleshooting activities of one ISP can be difficult. Extending this to multiple ISPs can be tricky. You should also realize that not all data centers allow access to all carriers and in some cases there may be only a limited number of circuit types available. Make sure you understand how your desired types of circuits and carriers will gain access to the facility before making a final data center decision. The relationship between carriers and ISPs in a CO leads to a variety of additional terminologies you'll need to know: LOA-CFA (Letter of Authority and Customer Facility Assignment): This document does two things. Firstly, it allows a carrier to have access to another carrier's facility to do work (LOA). Secondly the carrier that issues the document also provides a facility assignment (CFA) which indicates the specific interconnection point within the CO for the other carrier to use. Work cannot proceed without a LOACFA for the local loops. The more local loops you have, the more LOA-CFAs are required. It is important to keep a very close eye on this process. DLR (Design Layout Record): This document describes all the details of the circuit path from one end to the other. It can include physical information such as location, floor, row, rack, panel and port. It can also refer to virtual circuits, in other words, circuits that are securely shared with other customers, such as a channelized DS3. A DLR can also mention interconnections with other known circuits, which can help reduce the complexity of the document. You should always verify that a DLR has been created on time in order for it not to hold up the rest of your operation. FOC (Firm Order Commitment): It may sound rude, but FOC is a common term used in the industry. It is the date your carrier will commit to having a fully functional circuit delivered to you. Always ask what additional tasks will be required after the FOC date. You will almost certainly have to coordinate your engineers and those of the carrier to harmonize and test their configurations before data flows correctly. It is very possible for carriers to test their local loops correctly but make a mistake on the CFA with an incorrect cross-connection. MPOE (Main Point of Entry): Carriers and ISPs need to deliver data circuits to a specific room at a business address. It is typically the same room in which all telephone lines enter the building. MDF (Main Distribution Frame): Is usually a rack in the MPOE in which carriers will install the equipment required to terminate the circuit's local loop coming from the CO. This rack and equipment is usually the property of the carrier / ISP. Your equipment will usually connect to the MDF gear through a patch panel provided by you carrier / ISP. IDF (Intermediate distribution frame): In buildings with multiple tenants it is common to extend connectivity from the MPOE to each tenant's premises. Each tenant location, (eg. a server room or the location of their PBX) will have their own IDF for their own equipment. Connectivity between gear in the MDF and the IDF is usually achieved by using patch panels. Data center Cross-connects: A carrier or ISP will deliver your circuit to the MPOE, but you'll need to have a cross-connect created to link your server room's IDF to the MPOE's MDF. Remarkably, data centers often charge for this accessibility on a per circuit basis. It can be an unexpected hidden cost. With the knowledge of these terminologies you should be in a much stronger position when talking to your ISP and carriers.

IP Address Ownership In a data center environment you will normally request a block of IP addresses (the data equivalent of a telephone number) from your ISP for use by your servers. The ISP will assign a range of addresses to you and will configure their equipment to route traffic to this range via the data circuit they provide. There is a disadvantage to this. If you cancel your ISP data circuit, you will lose the IP addresses they assigned to you. This could force you to reassign brand new IP addresses to your servers. Always consider applying for your own IP addresses from your Regional Internet Registry (RIR). Here is a useful list of RIRs you can use for your area:

64



1. AfriNIC (African Network Information Centre) - Africa region 2. APNIC (Asia Pacific Network Information Centre) - Asia Pacific region 3. ARIN (American Registry for Internet Numbers) - Americas and Southern Africa 4. LACNIC (Regional Latin-American and Caribbean IP Address Registry) - Latin America and some Caribbean 5. RIPE NCC (Réseaux IP Européens Network Coordination Centre) - Europe and surrounding areas will recognize your operation as being similar to that of an ISP and will assign you your own AS and IP addresses. The circumstances for doing so are slightly different for each affiliate but the main factors are that you can prove that your routing policy is different from that of your ISP and/or that your connectivity requires links to multiple ISPs. If you cannot obtain your own IP block then you will have to ensure that all your applications use DNS names to refer to other servers in your environment and not their actual IP addresses. When new IP addresses are required, you can just modify the DNS name to map to the new address. This minimizes the impact of forced IP address changes on your operation.

Routing Protocols Internet routing can be quite complicated and you will often need a network engineer to configure your equipment to get access. This section will provide an overview for project managers of the most common Internet routing challenges data center based web sites face. It will provide insights into what can be done if things go wrong during your data center relocation. ISPs usually use two methods to provide internet access to their clients. The first is by providing a simple default gateway through which all network traffic should pass. This is the usual option when only a single link is provided. The second method relies on the border gateway protocol (BGP) and is used primarily when Internet connectivity is provided via multiple ISP links.

Border Gateway Protocol BGP is a dynamic protocol that can be adjusted relatively easily to influence traffic to and from your site in order to reduce bandwidth costs when your ISPs charge different rates, or to divert excess traffic from an overloaded circuit to a lesser utilized one. Unlike the configuration of a static route that can never change even if a link fails, BGP routes adjust themselves automatically depending on the availability of network links to reach target destinations. This section will cover BGP for use by project managers in some detail and Table A3.2 summarizes many of the terms that will be used later.


65

Table A3.2 - Common BGP Routing Terms

Term

Description

BGP Autonomous System (AS)

A BGP routing management domain usually owned by ISPs. Autonomous systems are assigned blocks of IP addresses which the ISP advertises to neighboring autonomous systems. The ISP is also responsible for the routing of traffic destined to their AS or passing through it to another AS.

Autonomous System Number (ASN)

A unique number assigned to the ISP for their autonomous system.

AS Path

A sequential list of ASs traffic must pass through in order to reach its destination network.

AS Path Prepending

A method of repeatedly adding on your AS number to the beginning of the AS path to your network to bias traffic away from the link that is advertising the prepended list.

Local Preference

A method of biasing the desirability of routes to the internet via a particular link in favor of an alternative one within your BGP AS.

Multi-Exit Discriminator (MED)

A method in which an ISP, with multiple links to your AS, can bias your routers to select one of its paths to the Internet over another.

With BGP, each ISP is provided with a BGP autonomous system (AS) number from the Internet Assigned Numbers Authority (IANA). The ISP then associates the IP addresses it owns to this AS. Routes are exchanged with other ASs in the form of "I am AS number X and in my AS I have the following networks". This results in BGP routers having long lists of all the available networks on the Internet tied to a sequence of ASs that need to crossed in order to get to each one. This sequence is called an AS path list. BGP routers update their neighbors of changes they detect in the Internet. If a BGP router loses connectivity with a peer responsible for advertising networks for a particular AS, it then notifies its remaining neighbors of the failure and instructs them to remove their routes to the failed AS from their routing tables. ISPs can advertise default routes to your routers via BGP. This can be useful when your equipment doesn't have sufficient memory to store the entire Internet routing table. Some manufacturers recommend a minimum of 512 KB of RAM to support full routes. No matter what types of routes you receive you can influence how traffic leaves your site with a number of commonly used techniques. If the links terminate on the same router you can use a system of weighting to route traffic completely over one link versus the other. Weights aren't exchanged between routers, so when the links terminate on different routers within your control you'll need to use BGP's local preference feature help them negotiate the preferred link. When both your links are provided by the same ISP, you can also have them advertise a unique multi-exit discriminator (MED) metric value in the advertisements on each link which will bias BGP on your router to route its traffic on one link versus the other. The methods previously discussed only refer to outbound traffic. Inbound traffic can be influenced too. One method uses AS path prepending in which you repeatedly add on your own AS number in your BGP advertisements. This lengthens your AS path list without making the traffic pass through any additional ASs. Prepending can be applied on a per link basis so that internet routers will feel that the AS path to your network on your preferred link is much shorter than the one to your network via the less favorable link.


66


These modifications don't have to apply to all Internet routes. You can bias traffic on a per-network and per-AS basis. This can be very useful. Say for example you have to email a weekly newsletter to thousands of customers but the additional traffic saturates one of your ISP links, you can use local preferences to make traffic to Hotmail, MSN and Yahoo! go through the original link, but traffic to AOL and Gmail pass through the other. Another common example would be a situation in which BGP automatically passes most of your outbound traffic over your most expensive link. You can use some of the techniques mentioned to make BGP favor the cheaper link for your traffic until your safe link bandwidth threshold is reached. You can usually guess the most popular ISPs from which web surfers would be coming, if not there are automated tools such as netflow on routers, and webalizer on web servers, that can provide more accurate insights. You can also figure out an AS number manually using the method in the following section.

Determining a BGP Autonomous System Number Determining the AS number of an ISP or mail service manually is usually straight forward. In this case I'll attempt to determine the AS to which the IP address of mail.aol.com belongs. 1. Use the nslookup or host command on a Windows or Linux server to determine the IP address of mail.aol.com [root@bigboy tmp]# host mail.aol.com mail.aol.com has address 64.12.168.119 mail.aol.com has address 64.12.193.249 mail.aol.com has address 205.188.160.249 [root@bigboy tmp]#

2. Use a search engine to find a site that will provide access to "BGP looking glass" routers. Log on to one of the looking glass routers listed on the site. 3. Enter one of the AOL IP addresses, in this case 64.12.168.119, and select "BGP", not "BGP summary". Click on the submit button and you will get output looking like this. TELIA (1299) AOL (1668) 8176, (aggregated by 8176 172.21.44.GENUITY/BBN (1)) 213.248.86.53 (metric 7) from 216.218.252.149 (216.218.252.149) Origin IGP, metric 46, localpref 100, valid, internal, atomic-aggregate Community: 6939:2000

The output shows that the AS path list is 1299, 1688, 8176. This means to get to mail.aol.com the looking glass router had to pass through AS 1299, then 1688 and finally AS 8176. The final AS, 8176, is the AS for mail.aol.com. You will now have to do this again for all the other IP addresses returned by the hosts command.

Administrative Tasks Needed to Advertise BGP Routes Network engineers will have to configure BGP on their routers, but the project manager will have to contact the ISP to make sure they are prepared to receive your routes. You will have to inform them ahead of time of your AS number, the networks you wish to advertise and the possibility of using AS path prepending. Once they receive this they will configure their equipment and then provide you with: 1. A data circuit. 2. IP address assignments for both your and their equipment connected to the circuit. 3. Their BGP AS number. Your network engineer will then be able to configure your equipment to provide correct BGP connectivity to the Internet. Note: When you use multiple ISPs, make sure your network engineer's BGP configuration guarantees that data traveling from ISP #1 to ISP #2 doesn't pass through your AS. If this happens, you will find yourself paying for traffic that wasn't destined to your site. The volume of traffic passing through your AS could cripple your data circuits too.


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Conclusion Data center ISP selection is a very important part of any relocation activity. This Appendix has provided a summary of the issues that need to be addressed in the process and will make the overall task much simpler to complete. Activity checklists are provided in Appendix I to help facilitate this further.

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Data Center Relocation

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