An SAP Basis administrator is migrating an SAP ERP system from an on-premises environment to AWS. The system uses an SAP HANA database. The migration must have minimal downtime. The administrator plans to use SAP HANA System Replication (HSR) to synchronize data to an AWS HANA instance. However, the network latency between on-premises and AWS is consistently around 50 ms. What should the administrator do to ensure that HSR can maintain synchronization without impacting source system performance?
Asynchronous replication does not wait for acknowledgment, so source performance is unaffected; suitable for high-latency links.
Why this answer
With 50 ms network latency, synchronous replication would block source transactions while waiting for acknowledgment from the target, severely impacting performance. Asynchronous mode with full sync disabled allows HSR to send log buffers without waiting for the target to confirm, ensuring source system performance is unaffected while still maintaining eventual consistency for migration.
Exam trap
The trap here is that candidates confuse synchronous replication with 'safer' replication, not realizing that high latency makes synchronous mode impractical for performance-sensitive source systems, and that 'full sync' is a separate HSR parameter controlling whether the secondary must be fully in sync before the primary commits.
How to eliminate wrong answers
Option A is wrong because synchronous replication with a lower sync timeout would cause frequent timeouts and transaction failures, not avoid blocking. Option C is wrong because increasing the replication timeout in synchronous mode still blocks source transactions during the wait period, only delaying the timeout event. Option D is wrong because delta merge operations are a HANA internal memory optimization unrelated to replication data transfer; they do not reduce the amount of data sent via HSR.