Explanation
The exhibit shows a JSON object that contains the replication status of a database in a Secrets Manager cluster. Secrets Manager is a secrets management solution that securely stores and manages secrets and credentials used by applications, DevOps tools, and other systems. Secrets Manager can be deployed in a cluster mode, which consists of a Leader node and one or more Follower nodes. The Leader node is the primary node that handles all write operations and coordinates the replication of data to the Follower nodes.
The Follower nodes are read-only nodes that replicate data from the Leader node and serve requests from clients and applications that need to retrieve secrets or perform other read-only operations.
To confirm that the Follower has a current copy of the database, you can compare the pgcurrentxlog_locationlocation from the Leader to the Follower you need to validate against. The pgcurrentxlog_locationlocation is a property that indicates the current position of the write-ahead log (WAL) in the database. The WAL is a mechanism that records all changes made to the database in a sequential log file, before they are applied to the actual data files. The WAL ensures the durability and consistency of the database in case of a crash or a power failure. The WAL also enables the replication of data from the Leader node to the Follower nodes, by streaming the WAL records to the Follower nodes and applying them to their local databases.
By comparing the pgcurrentxlog_locationlocation from the Leader to the Follower, you can determine how far behind the Follower is from the Leader in terms of the WAL records. If the pgcurrentxlog_locationlocation values are identical or very close, it means that the Follower has a current copy of the database, and that the replication is working properly. If the pgcurrentxlog_locationlocation values are different or far apart, it means that the Follower has an outdated copy of the database, and that there is a replication lag or a replication failure. In that case, you may need to troubleshoot the replication issue and resolve it as soon as possible.
References = Secrets Manager Cluster Installation; Secrets Manager Cluster Configuration; Write-Ahead Logging - PostgreSQL Documentation