A review on v62-006: failover-ready validation steps doc - + Next, check that the logical replication slots identified above exist on + the standby server. This step can be skipped if + <varname>standby_slot_names</varname> has been correctly configured. +<programlisting> +test_standby=# SELECT bool_and(synced AND NOT temporary AND conflict_reason IS NULL) AS failover_ready + FROM pg_replication_slots + WHERE slot_name in ('sub'); + failover_ready +---------------- + t +(1 row)
This query does not ensure that all the logical replication slots exist on standby. Due to the 'IN ('slots')' check, it will return 'true' even if only one or a few slots exist.