HANA SLT(SAP Landscape Transformation) Replication Errors and Resolution Steps

[jagadeesh_mandepudi2]

Hi All

In this blog we are going to discuss SLT replication errors and resolution steps.

Basic Concepts and System Landscape Options:

The SAP Landscape Transformation (SAP LT) Replication Server is the SAP technology that allows you to load and replicate data in real-time from ABAP source systems and non- ABAP source systems to an SAP HANA environment. The SAP LT Replication Server uses a trigger-based replication approach to pass data from the source system to the target system.

In order to replicate data, you must first define the parameters that the SAP LT Replication Server will use to replicate data from one or more source systems to one or more target systems. You specify this information in a Configuration. A configuration contains information about the source system, the target system, and the relevant connections. You define configurations in the SAP LT Replication Server.

You use a configuration to load and replicate data from one source system to one target database schema of a HANA system (1:1), or from multiple source systems to one target database schema of an SAP HANA system (N:1). Furthermore, it is possible to load and replicate data from one source system to multiple (up to 4) target database schemas of one or more HANA systems (1:N). You can also specify the type of data load and replication - either in real-time, or scheduled by time or by interval.

Note: Above Basic concepts content was copied from SAP document - SAP Landscape Transformation Replication Server Operations Guide for quick background.

Replication Errors and Resolution:

1. In case of issues with master job build – we observe that no table being replicated and new table replication also does not happen.

When we try to activate SLT configuration it shows configuration active but number of active replication jobs shows zero then follow below steps to get it back to normal.

• We need to stop all configurations and make sure there are no active master job (/1LT/IUC_REP_MSTR) exists in SM37.


• Now if you start one configuration at a time and see your master job will be build and up and running.


• Repeat this step for remaining configurations.

2. If you see tables under Data Transfer Monitor with block processing steps as “Load / Replication blocked” but not “Failed”.

• Log into LTRC Transaction and Deactivate all configurations.


• Go to transaction SM37 and make sure all SLT jobs are stopped that start with naming convention /1LT/*.


• Log back in to LTRC | Select your configuration or MT_ID | Processing Steps Tab | 'Delete Load / Replication Objects' (this will delete all load/replication objects).


• To confirm all objects have been deleted go to the Data Transfer Monitor Tab | and all tables should disappear in this tab.


• Go back to Processing Steps Tab | Execute ‘Define Load/Replication Object’ for all tables.


• Next execute the 'Generate Runtime Modules' for all tables.


• Next execute the 'Start Range Calculation' for all tables.


• Go back to Data Transfer Monitor Tab and you see all the tables back in this tab.  Plus confirm that you see a "X" under the 'Defined', 'Generate', and 'Calculated' for all the tables.

3. If you see tables under Data Transfer Monitor with block processing steps as “Load / Replication blocked” but “Failed” or Tables which are under failed status.

• Log into LTRC Transaction and Deactivate all configurations.


• Go to transaction SM37 and make sure all SLT jobs are stopped that start with naming convention /1LT/.....


• Log back into LTRC | Select your configuration or MT_ID | Expert Functions |Reset Status for Triggers and Logging Tables (Check boxes needs to be checked based on table status example if Table is in failed status then only reset Failed flag, still not works reset all of them)


• Log back into LTRC | Select your configuration or MT_ID | Expert Functions |Reset Status of Tables and Synonyms (Check boxes Table/Sync. Sender and Table/Sync. Receiver needs to be checked)


• Log back in to LTRC | Select your configuration or MT_ID | Processing Steps Tab | 'Delete Load / Replication Objects' (this will delete all load/replication objects).


• To confirm all objects have been deleted go to the Data Transfer Monitor Tab | and all tables should disappear in this tab.


• Log back in to LTRC | Select your configuration or MT_ID | Processing Steps Tab | Create Logging Tables' (this will create logging table if existing had issues).


• Log back in to LTRC | Select your configuration or MT_ID | Processing Steps Tab | Create Database Triggers (this will create triggers).


• Log back in to LTRC | Select your configuration or MT_ID | Processing Steps Tab | Create Tables and Synonyms' (this will create tables and synonyms).


• Go back to Processing Steps Tab | Execute ‘Define Load/Replication Object’ for all tables.


• Next execute the 'Generate Runtime Modules' for all tables.


• Next execute the 'Start Range Calculation' for all tables.


• Go back to Data Transfer Monitor Tab and you see all the tables back in this tab.  Plus confirm that you see a "X" under the 'Defined', 'Generate', and 'Calculated' for all the tables.

4. If you see any table replication not working and record count is not matching with source system with portion error as shown below.

• SAP suggested only option is after trying with reset and create options(Points 2&3) still not working then we have to go for re-replication in case of portion errors.

5. If you see below error for any of the tables, it might be issue with table enhancements or source system upgrade impacted this table.

• For this issue we need to delete existing logging table in source system as structure been changed, so go to source system and execute T-code “IUUC_REMOTE”


• It’s very powerful T-code so please look for respective option which is under “Expert Functions” tab and click on “Delete Logging Table” option.


• It will show you screen where you can see default selection filled we need to clear otherwise it will delete all logging tables. Please provide your selected logging table and press execute.


• Now come to SLT system and re-replicate the table.

6. If any of SLT table throws below error and after performing all reset options mentioned in this document still throws same error then we have to go for re-replication.

7. If master job getting canceled with below error.

Check SAP note - 2375857 - SLT/MWB: Internal error when generating object GLOBAL

• Implement report dmc_restore_project_global in the system where the problem occurs.


• Execute this report from SA38. It will run directly without selection screen, and will restore the missing table record.


• After implementing the report, maintain its text elements in transaction SE38, as follows:

EXI Project GLOBAL already exists

FAI Creation of project "GLOBAL" failed due to duplicate key

NOR PANIC: The global rules are also missing - will not be restored!!

SUC Project "GLOBAL" was successfully created.

8. If any one of the table had issue under one “POOL” table then we need to follow below steps.

• If we are working on tables which are type “POOL” then we need to make sure we are selecting all tables under that pool table, if you take example of ATAB this is the pool table for almost around 50 tables starting with T*. Since all these tables had same logging table so we need to perform above resolving steps for all the tables.

Important T-codes/Tables:

IUUC_REMOTE: T-code in source system to delete logging tables or triggers. Make sure you unselect default selection and select only required ones.

LTRO - SLT Monitoring.

IUUC_TABLES - It will show you table and its logging table details.

IUUC_LOG_APPLTAB  - Table will show logging table info in source side.

 

Thanks

Jagadeesh Mandepudi