AWS Certified Database – Specialty — Question 243

A company uses an Amazon RDS for PostgreSQL database in the us-east-2 Region. The company wants to have a copy of the database available in the us-west-2 Region as part of a new disaster recovery strategy.

A database architect needs to create the new database. There can be little to no downtime to the source database. The database architect has decided to use AWS Database Migration Service (AWS DMS) to replicate the database across Regions. The database architect will use full load mode and then will switch to change data capture (CDC) mode.

Which parameters must the database architect configure to support CDC mode for the RDS for PostgreSQL database? (Choose three.)

Answer options

• A. Set wal_level = logical.
• B. Set wal_level = replica.
• C. Set max_replication_slots to 1 or more, depending on the number of DMS tasks.
• D. Set max_replication_slots to 0 to support dynamic allocation of slots.
• E. Set wal_sender_timeout to 20,000 milliseconds.
• F. Set wal_sender_timeout to 5,000 milliseconds.

Correct answer: A, C, E

Explanation

The correct options A, C, and E are necessary for enabling CDC mode. Setting wal_level to logical (A) allows for logical decoding, which is essential for CDC. The max_replication_slots (C) must be set to a minimum of 1 to accommodate DMS tasks. The wal_sender_timeout (E) ensures that the connection remains active during replication. Options B and D are incorrect as they do not meet the requirements for CDC mode, and option F provides an inadequate timeout setting.