Symmetrix Imp Questions for Interview

DMX-4 Interview Questions · What is the difference between DMX-3 and DMX-4? · What is the difference between DMX-4 and DMX-950? · How many Cache directors, Front-end directors and Back-end directors we can use in DMX-4? · What are the different types of Front-end directors and the purpose of each one? · What is the FAN-IN and FAN-OUT ratio of DMX-4? · Explain Rule 17 in DMX? · What are the Management Tools for DMX? · What are the major components of System Bay and Storage Bay? · Explain Enginuity Operation layers · How do you calculate number of cylinders for 50GB LUN? · What is the maximum hyper size in DMX-4? · How many hypers can create in a Single disk? · How many members can contain in one meta? · How many LUN IDs available per port? · What Dynamic LUN addressing? · How do you add a new member to the existing Meta? · What is stripping and what is Concatenating? · What are the DMX-4 supported disk types, no. of disks and maximum capacity? · Briefly explain the DMX-4 supported Device types? · What are the RAID levels DMX-4 Supports? · What are Vault drives and Hot Spare? · What is Preview, Prepare and Commit while using Symconfigure command? · How do you check the back-end Operations on Symmetrix Array? · How do you check the failed disks in the Symmetrix Array? · What are the service states of a device · How do you reserve the devices? · What is Tiering and how do you create the Disk Groups · How do you check the free space by Disk group and Array as whole? · How do you check the particular disk is connected to which DA Port and it is resides in particular DAE? · What is drive looping? · How do you check the particular device is connected to which Host? · How do you check the total allocated storage of a Host? · Host is unable to see the storage, what may be the problem? · What is VCMDB and How do you take the backup? · How do you list the Hosts which are connected to particular director port? · How do you check the number of storage bays connected to the system bay and number of disks in each storage bay? · How do you check the devices which are mapped to FA but not masked to any host? · How do you check the login hosts in the Array? · What is pre check list to assign to storage to the host?

· Explain step by step to provide storage to the Host? · What is Thin Provisioning? · How do you create thin pools and thin devices? · What are the steps for storage reclamation? · How many mirror positions RAID-1 and RAID-5 will occupy? · How do you increase the mirror positions? · How do you convert the One device type to another? · What is FA Port Flag and how do you set the FA port flags? · How do you setup the Symmetrix metrics? · How do you check the configured environmental variables? · Can windows, Linux, Solaris share the same FA in DMX? · What are the External locks and how to check? · How to monitor performance of EMC Symmetrix? · How do you check performance statistics of a particular director port? · How do you check the cache activity of selected front-end directory? · How do you check the back-end I/O requests of selected disk? · What are the available performance information types in SYMSTAT command? · What is symmetrix optimizer and how it works? · What is Symmetrix QoS and how it works? · What is the purpose of Symmetrix Change Tracker? · What is Dynamic Cache Partitioning? · What are the logs available at host-end and on symmetrix array? · How do you monitor the real time events on symmetrix array with example? · How do you track the history of events on symmetrix array with example? · How do you check the audit logs on symmetrix array? · How do you activate the auditing on symmetrix array? · What is Symmetrix ACL? · Explain step by step to setup the access controls on symmetrix array? · How do you take the backup of ACLs? · What is Symmetrix User Authorization? · Explain step by step to setup user authorization on symmetrix array? · How do you perform backup and restore user authorization information? · What is Read Hit and Write Miss? · What is the purpose of bin file in SAPAPI database? · What are the services of symcli? · Explain step by step procedure to setup new host? · What are the Symcli Base Management Commands? · How do you prepare the Storage Capacity planning reports by host wise? · What are the Symmetrix Business Continuity Tool · By using what symcli command we can check the HBA details and physical details · What are the business continuity tools for symmetrix array?

Always wanted to know what is behind the serial number of a VMAX Array? I recently found out that the serial number of the VMAX contains at least 2 parameters that can tell you more about the box. If I find more I will update this article. For starters how cool is it to say “Oh that’s a 40K” when you only read the serial? Here is a short list: 

VMAX-40K – ****57*****

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VMAX-20K – ****26*****

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VMAX-10K(old) – ****59*****

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VMAX-10K(new) – ****87*****

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VMAX-SE – ****49*****

Next where was it build? Knowing EMC, somewhere in your region. But with only 3 manufacturing facilities building VMAX that would mean USA, Ireland and China. Anyone know where in China? The first 2 letters of the serial number shows the build factory. HK means Hopkinton (USA), CK means Cork (Ireland) and CN means somewhere in China. Now to find out the same for VNX and VPLEX, etc.