Introduction
SAP Landscape Transformation (SLT) is an essential data replication technology used for real-time or scheduled data transfer between SAP and non-SAP systems to SAP HANA. SLT enables businesses to manage data efficiently, ensuring data consistency and integrity. This guide answers common questions about SAP SLT and offers insights into its functionality, configuration, and troubleshooting.1. Understanding Data Transfer Jobs and Background Work Processes
How does the number of data transfer jobs relate to background work processes?
Each data transfer job in SAP SLT requires one background (BGD) work process in the replication server. The configuration parameter Data Transfer Jobs limits the maximum number of data load jobs per Mass Transfer ID (MT_ID).Minimum Background Jobs Required:
- One Master Job
- One Master Controller Job
- At least One Data Load Job
- One Additional Job (for migration, access plan calculation, or configuration changes)
2. Configuration Example for Data Transfer Jobs
Scenario:
If the parameter Data Transfer Jobs is set to 04 for configuration SCHEMA1, and a Mass Transfer ID 001 is assigned, the system will run:- 1 Master Job: IUUC_MONITOR_SCHEMA1
- 1 Master Controller Job: IUUC_REPL_CNTR_001_0001
- Up to 4 Parallel Jobs: DTL_MT_DATA_LOAD_001_01/~02/~03/~04
Performance Considerations:
- If multiple tables are selected for replication simultaneously, the system may lack enough background jobs.
- Increase the number of initial load jobs to optimize performance.
- Use Advanced Replication Settings (IUUC_REPL_CONT) to fine-tune data load for high-volume tables.
3. What Happens After SLT Replication is Completed?
User & Privileges:
- 1 User
- 1 Privilege
Roles Created:
- <REPLICATION_SCHEMA>_DATA_PROV
- <REPLICATION_SCHEMA>_POWER_USER
- <REPLICATION_SCHEMA>_USER_ADMIN
- <REPLICATION_SCHEMA>_SELECT
Stored Procedures Created:
- RS_GRANT_ACCESS
- RS_REVOKE_ACCESS
Tables Created:
- DD02L
- DD02T
- RS_LOG_FILES
- RS_MESSAGES
- RS_ORDER
- RS_ORDER_EXT
- RS_SCHEMA_MAP
- RS_STATUS
4. Different Replication Scenarios in SAP SLT
Replication Types:
- Load: Performs a one-time initial data load without ongoing replication.
- Replicate: Combines initial load and real-time replication.
- Stop: Ends the replication and deletes database triggers/logging tables.
- Suspend: Temporarily halts replication without deleting database triggers.
- Resume: Restarts replication for a previously suspended table.
Key Considerations:
- Before starting replication, tables DD02L, DD02T, and DD08L must be loaded as they contain metadata information.
- Logging tables in the source system may grow if replication is suspended for long periods.
5. Managing Long-Term Suspension or System Outages
What happens if replication is suspended for a long time?
- Logging tables in the source system increase in size, consuming more storage.
- To avoid excessive logging, pause the replication by stopping schema-related jobs.
6. Data Storage Considerations in SAP HANA
Is table size in SAP HANA the same as the source system?
No, SAP HANA uses data compression, reducing storage requirements compared to the source system.When should you use table partitioning?
If a table in HANA exceeds 2 billion records, partition it using Advanced Replication Settings (IUUC_REPL_CONT).7. Defining Transformation Rules in SLT
Transformation rules are set using Advanced Replication Settings (IUUC_REPL_CONT) under the IUUC ASS RULE MAP tab. These rules enable:- Data format adjustments
- Field transformations
- Conditional mappings
8. Considerations for Non-SAP Source Systems
How does SLT work with non-SAP systems?
- Connect via a direct database link instead of RFC.
- Require a primary key for replication.
- Do not replicate metadata tables (DD02L, DD02T)—they are only initially loaded.
- May need transformation rules for database-specific formats.
9. Common Issues in SLT Configuration
Potential Issues & Solutions:
| Issue | Solution |
|---|---|
| Missing DMIS_2010 Add-On | Install the required DMIS_2010 add-on in the source system. |
| Incorrect RFC User Role | Ensure RFC user has SAP_IUUC_REPL_REMOTE role. |
| Incorrect SLT User Role | Assign SAP_IUUC_USER for SLT system. |
| Incorrect Logon Credentials | Verify username and password. |
10. Ensuring Data Consistency Between Source and SAP HANA
SAP SLT tracks every change in dedicated logging tables. Once data is successfully replicated to SAP HANA, the corresponding log entry is deleted.Key Features for Data Consistency:
- Transparent replication status tracking
- Commit statements ensure data consistency between source and HANA
11. Does SLT Support Data Compression?
Yes, SLT supports data compression, leveraging RFC connections to minimize the amount of data transferred. This ensures efficient storage and faster replication.Frequently Asked Questions (FAQs)
1. What is the difference between "Replicate" and "Load" in SLT?
Replicate: Includes both an initial load and real-time replication.Load: Transfers data only once without ongoing replication.
2. How can I improve SLT performance for large tables?
Use Advanced Replication Settings (IUUC_REPL_CONT).Increase the number of initial load jobs.
Partition tables exceeding 2 billion records.
3. What happens if I stop replication?
Database triggers and logging tables are deleted.If replication needs to be restarted, a new initial load is required.
4. Can I use SLT for non-SAP source systems?
Yes, but:- Only SAP-supported databases are compatible.
- Data transformation rules may be required.
5. How do I monitor SLT replication?
Use the Configuration and Monitoring Dashboard to track job status and resolve issues.6. What is the role of logging tables in SLT?
Logging tables store real-time changes and ensure data consistency between the source and SAP HANA.Conclusion
SAP Landscape Transformation (SLT) is a powerful tool for real-time data replication to SAP HANA. By understanding its configuration, replication types, and performance optimization strategies, businesses can ensure seamless data integration. Following best practices and addressing common challenges will enhance SLT efficiency and reliability.