Qs. What are the different types of replication techniques? There are 3 types of replication techniques: 1. SAP Landscape Transformation (SLT) 2. SAP usiness !"#ects $ata Ser%ices (!$S) 3. SAP &A'A $irect tractor *onnection ($+*) Note: There is one more replication technique called Sy"ase replication. ,t -as part of initial offerin for &A'A replication/ "ut not positioned 0 supported anymore due to licensin issues and compleity and mostly "ecause SLT pro%ides the same features.
Qs. What is SLT? The SAP Landscape Transformation (LT) eplication Ser%er is the SAP technoloy that allo-s us to load and replicate data in realtime from SAP source systems and nonSAP source systems to an SAP &A'A en%ironment. The SAP LT eplication Ser%er uses a trier"ased replication approach to pass data from the source system to the taret system.
Qs. What is the advantage of SLT replication? 1. 2. 3. . 4.
Advantages: SAP LT LT use ses s tr tri ie err "a "ased ap approach ch.. Tr Tri i er r"a "as sed app pprroach ha has no no measurea"le performance impact in source system. ,t pr pro%ides transformation and filterin capa"ility ty.. ,t all alloo-s s rea real lti time me (an (and d sch sched edul uled ed)) dat data a rep repli lica cati tio on/ rep repli lica cati tin n on only ly re rele le%a %ant nt da data ta into &A'A from SAP and nonSAP source systems. ,t is fully interated -ith &A'A Studio. epl e plic icat atio ion n fro from m mul multi tipl ple e sou sourc rce e sy syst stem ems s to to one one &A &A'A 'A sy syst stem em is al allo lo-ed ed// als also o from one source system to multiple &A'A systems.
Qs. Is it possible to use a replication for multiple sources and target SA !A"A systems? 1
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5es/ the SAP LT eplication Ser%er supports "oth 1:' replication and and ':1 replication. 6ultiple source system can "e connected to one SAP &A'A system. !ne source system can "e connected to multiple SAP &A'A systems. Limited to 1: only.
Qs. Is there any pre#requisite before creating the configuration and replication? 1. 2. 3. . 1. 2.
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For SAP source systems: $6,S addon must "e installed in SLT replication ser%er. An 7* connection "et-een the SAP source system and the SAP LT eplication Ser%er has to "e esta"lished. 8ser for 7* connection must ha%e the role ,88*9PL96!T assined. $o not use a $$,* user for 7* connection. For non-SAP source systems: $6,S addon is not required. A data"ase user has to "e created -ith appropriate authoriations in ad%ance and esta"lish the data"ase connection "y usin transaction $*! in the SAP LT eplication Ser%er. nsure the data"asespecific li"rary components for the SAP ;.2< L or +T =ernel are installed in the SAP LT eplication Ser%er.
Qs. What is $onfiguration and %onitoring &ashboard? 2
,t is an application that runs on SLT replication ser%er to specify confiuration information (such as source system/ taret system/ and rele%ant connections) so that data can "e replicated. ,t can also use it to monitor the replication status (transaction LT). Status 5ello-: ,t may occur due to triers -hich are not yet created successfully. Status ed: ,t may occur if master #o" is a"orted (manually in transaction S63;).
Qs. What is advanced replication settings 'transaction I(($)*+L)$,"T-? • • •
The Ad%anced Settins (transaction ,88*9PL9*!'T) allo-s you to define and chane %arious ta"le settins for a confiuration such as: Partitionin and structure chanes for taret ta"les in &A'A Ta"lespecific transformation and filter rules Ad#ustin the num"er of #o"s (and readin type) to accelerate the load0replication process
Qs. What is Latency? ,t is the lenth of time to replicate data (a ta"le entry) from the source system to the taret system.
Qs. What is logging table? A ta"le in the source system that records any chanes to a ta"le that is "ein replicated. This ensures that SLT replication ser%er can replicate these chanes to the taret system.
Qs. What are Transformation rules? • • •
A rule specified in the Ad%anced eplication settins transaction for source ta"les such that data is transformed durin the replication process. ample you can specify rule to *on%ert fields 7ill empty fields S=ip records
Qs. What happens hen you set#up a ne configuration? >hen a ne- confiuration in the SAP LT eplication Ser%er is created/ the data"ase connection is automatically created alon -ith a schema ?8,$ and 6ass transfer id (6T9,$). A schema ?8,$ ensures that confiurations -ith the same schema name can "e created. The 6ass transfer ,$ is used in the namin of SLT #o"s and the system can uniquely 3
identify a schema. The mappin of mass transfer ,$s and related schema are stored in the SLT control ta"le $6*96T9&A$ in the SAP LT eplication Ser%er.
Qs. What are the /obs involved in replication process? 1. 2. 3. . 4.
7ollo-in #o"s are in%ol%ed in replication process: 6aster @o" (,88*96!',T!96T9,$B) 6aster *ontrollin @o" (,88*9PL,*9*'T96T9,$B) $ata Load @o" ($TL96T9$ATA9L!A$96T9,$B92diitsB) 6iration !"#ect $efinition @o" (,88*9$796,?9!@92diitsB) Access Plan *alculation @o" (A**9PLA'9*AL*96T9,$B92diitsB)
Qs. What is the purpose of master /ob 'I(($)%,"IT,*)0%T)I&1-? %ery 4 seconds/ the monitorin #o" chec=s in the SAP &A'A system -hether there are ne- tas=s and/ if so/ triers the master control #o"s. ,t also deletes the processed entries (tas=s) from ta"le S9!$ and -rites statistics entries into ta"le S9STAT8S (in the rele%ant schema in the SAP &A'A system).
Qs. What is the purpose of master controller /ob 'I(($)*+LI$)$"T*)0%T)I&1-? • • •
This #o" is scheduled on demand and is responsi"le for: *reatin data"ase triers and loin ta"le in the source system *reatin synonyms >ritin ne- entries in admin ta"les in SLT ser%er -hen a ne- ta"le is loaded0replicated
Qs. What is the purpose of &ata Load 2ob '&TL)%T)&ATA)L,A&)0%T)I&1)03digits1-? This #o" should al-ays "e acti%e. ,f the #o" does not complete successfully/ the master controller #o" restarts it.
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This #o" is responsi"le for: Loadin data (load) eplicatin data (replication) *hanin status fla for entries in control ta"les in the SAP LT eplication Ser%er
Qs. What is the purpose of %igration ,b/ect &efinition 2ob 'I(($)&+4)%I5),62)03digits1-? 4
This #o" defines the miration o"#ect of a specific ta"le (that you choose to load0replicate)/ -hich is the fundamental o"#ect for LT replication. The miration o"#ect definition should normally "e quite fast for all ta"les.
Qs. What is the purpose of Access lan $alculation 2ob 'A$$)LA")$AL$)0%T)I&1)03digits1-? This #o" calculates the access plan of a specific ta"le (that you choose to load0replicate)/ and the access plan is used for data load or replication. The access plan is also a fundamental o"#ect for the replication. 7or a normal sied ta"le/ access plan calculation should finish quite quic=ly (less than 1 minute) -hile lare ta"les miht ta=e up to se%eral hours to finish.
Qs. What is the relation beteen the number of data transfer /obs in the configuration settings and the available 65& or7 processes? ach #o" occupies 1 ?$ -or= processes in SLT replication ser%er. 7or each confiuration/ the parameter $ata Transfer @o"s restricts the maimum num"er of data load #o" for each mass transfer ,$ (6T9,$).
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A mass transfer ,$ requires at least "ac=round #o"s to "e a%aila"le: !ne master #o" !ne master controller #o" At least one data load #o" !ne additional #o" either for miration0access plan calculation0to chane confiuration settins in C*onfiuration and 6onitorin $ash"oardD.
Qs. If you set the parameter 8data transfer /obs9 to :; in a configuration 8S$!+%A<9= a mass transfer I& ::< is assigned. Then hat /obs should be in the system? • • •
1 6aster #o" (,88*96!',T!9S*&6A1) 1 6aster *ontroller #o" (,88*9PL9*'T9<<19<<<1) At most parallel #o"s for 6T9,$ <<1 ($TL96T9$ATA9L!A$9<<19 <10E<20E<30E<)
Qs. What happens after the SLT replication is over? The SLT replication ser%er creates 1 user/ roles/ 2 stored procedures and F ta"les. 1 8ser 1 Pri%ilee oles 1. PL,*AT,!' S*&6AB9$ATA9P!G • • •
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1. 2. 3. . 4. I. ;. F.
PL,*AT,!'9S*&6AB9P!>98S PL,*AT,!'9S*&6AB98S9A$6,' PL,*AT,!'9S*&6AB9SL*T 2 Stored procedures S9?A'T9A**SS S9G!H9A**SS F Ta"les $$<2L $$<2T S9L!?97,LS S96SSA?S S9!$ S9!$9+T S9S*&6A96AP S9STAT8S
Qs. What are the different replication scenarios? Different replication scenarios are: Load/ eplicate/ Stop/ Suspend and esume. Load: Starts an initial load of replication data from the source system. The procedure is a one time e%ent. After it is completed/ further chanes to the source system data"ase -ill not "e replicated. 7or the initial load procedure/ neither data"ase triers nor loin ta"les are created in the source system. $efault settins use readin type 3 ($9ST?T) -ith up to 3 "ac=round #o"s in parallel to load ta"les in parallel or su"sequently into the &A'A system. Replicate: *om"ines an initial load procedure and the su"sequent replication procedure (real time or scheduled). efore the initial load procedure -ill start/ data"ase trier and related loin ta"le are created for each ta"le in the source system as -ell as in SLT replication ser%er. Stop: Stops any current load or replication process of a ta"le. The stop function -ill remo%e the data"ase trier and related loin ta"les completely. !nly use this function if you do -ant to continue a selected ta"le other-ise you must initially load the ta"le aain to ensure data consistency. Suspend: Pauses a ta"le from a runnin replication. The data"ase trier -ill not "e deleted from the source system. The recordin of chanes -ill continue and related information is stored in the related loin ta"les in the source system.
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,f you suspend ta"les for a lon time the sie of loin ta"les may increase and ad#ust the ta"le space if required. Resume: estarts the application for a suspended ta"le. The pre%ious suspended replication -ill "e resumed (no ne- initial load required).
Qs. What happens if the replication is suspended for a long period of time or system outage of SLT or !A"A system? The sie of the loin ta"les increases.
Qs. !o to avoid unnecessary logging information from being stored? Pause the replication "y stoppin the schemarelated #o"s.
Qs. Will the table si>e in SA !A"A database and in the source system the same? 'o. As &A'A data"ase supports compression/ the ta"le sie in SAP &A'A may "e decreased.
Qs. When to go for table partitioning? ,f the ta"le sie in &A'A data"ase eceeds 2 "illion records/ split the ta"le "y usin portionin features "y usin CAd%anced replication settinsD (transaction ,88*9PL9*!'T/ ta" pae ,88*9PL9TAST?).
Qs. Where do you define transformation rules? y usin CAd%anced replication settinsD (transaction ,88*9PL9*!'T/ ta" pae ,88* ASS 8L 6AP)
Qs. Are there any special considerations if the source system is non#SA system? •
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The concept of trier"ased replication is actually meant for SAP source systems. ,n case of nonSAP system/ follo-in points should "e =ept in mind: There -ill "e a data"ase connection "et-een nonSAP source and SLT system instead of 7*. Source must ha%e primary =ey Ta"les $$<2L/ $$<2T -hich contains metadata are #ust initially loaded "ut not replicated. The read modules reside on SLT system. Ta"les -ith data"ase specific formats may need transformation rules "efore they are replicated. !nly SAP supported data"ases are supported as nonSAP source systems. 7
Qs. &oes SLT for SA !A"A support data compression li7e SA !A"A database? 5es/ this is automatically co%ered "y the 7* connection used for data replication from the SAP source system.
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