Missing WAL File live scenario in PostgreSQL and how to recover from it

 

            Missing WAL File live scenario in PostgreSQL and how to recover from it

If WAL files are missing on primary side then replication will break and this error message will be displayed in the log file.

Answer - 

When a standby requests a WAL segment that the primary has already recycled or which is missing from archive storage, the standby cannot continue recovery. PostgreSQL physical replication does not support skipping missing WAL files. The only recovery is to re-initialize the standby with a fresh base backup.

I simulate this scenario by stopping the standby, generating excessive WAL on the primary, manually removing old WAL files, and restarting the standby.”

On PROD-1

On Replica -

Took the fresh pg_basebackup and built the replica again.