Basic Understanding of SLT Replication Server

[sudhir_kumar22]

Basic Understanding of SLT Replication Server

What is SLT

SLT is the an ETL ( Extract , Transform , Load ) tool which allows us to load and replicate data in real-time or schedule data from SAP source system or Non SAP System into SAP HANA Database.

SAP SLT server uses a trigger-based replication approach to pass data from source system to target system.

Trigger based replication means the DB triggers happen whenever there is data populated in the logging table.

Advantages of SLT

• SLT permits real-time data replication as well as or schedule time data replication.


• SLT can replicate both Cluster tables and Pool tables.


• SLT replicates data and transforms into HANA format during the real time.


• SLT is integrated with HANA Studio


• SLT have table setting and rule settings with transformation capabilities.


• SLT have monitoring capabilities with SAP Solution Manager.

Architecture of SAP SLT server with SAP as source System:

DB triggers: Monitors for any events ( Insert , Delete , Modify , update etc ) that take place in Table( Application table ). DB triggers will be created on Source system.

Logging Tables: If DB triggers, then logging tables will stores triggered data, which is modified data in Application table. Logging tables will be created on Source System

Read Engine: Read engine will be responsible for reading the data from logging table and passing to SAP SLT Replication server.

Mapping and Transformation Engine: This will be responsible for structured transformation of data as per target HANA DB format.

 

Write Engine: Write Engine will be responsible for writing the data into HANA DB from SAP SLT Replication server.

Installation Types

Basic requirements for the SAP LT Replication Server:

• SAP NetWeaver 7.02 or greater


• SAP Kernel 7.20 patch level 110 or higher


• Unicode


• Same or higher SAP Basis release than all connected system

SAP SLT Replication Server can be installed as per below scenario

• Source system is SAP System: If Source system is, an SAP System then SLT Replication Server can be installed on its own as standalone or on the Source system itself.


• Source system is non-SAP system: If the Source system is non-SAP system then SLT Replication server can be installed only as a standalone and addition to that the DB connection will be used between non-SAP source system and SLT Replication server whereas with an SAP source system, RFC connection will be used.

How SLT Works

Below are the replication process which happens between Source System (SAP), SLT Replication server and HANA DB:

• RFC Connection need to be established between SAP Source system and SLT Replication Server.


• DB Connection need to be established between SLT Replication server and HANA DB.


• When the replicate option is executed first time for a table, System will load entire data that is in application table to HANA DB.


• Once the load completes, status will change from Load to Replicate.


• Once the status changed to replicated, the DB trigger and Logging table will be created in Source system. Logging table will keep storing the modified data as per the DB trigger.


• Read engine will read the data from logging table and send it to SLT Replication server using RFC connection.


• SLT Replication server transforms and formats the data as per the HANA format and Write engine sends the data to HANA DB using DB connection.

In the next blog I will discuss on the use of different options in LTRS and LTRC.