During testing, it was observed that internal server processes in Zabbix behave inconsistently when reconnecting to the database after a failover.

When a database node switch occurs, some internal processes produce the following sequence of logs:

1. PGRES_FATAL_ERROR (from the old database connection)
2. successful reconnection to another database node
3. "database connection re-established"

At the same time, other internal processes show a different behavior:

1. PGRES_FATAL_ERROR is logged
2. reconnection to another database node happens successfully
3. no "database connection re-established" log is produced

As a result, from an user perspective, it may look like some processes failed or did not recover correctly, even though they continue working normally.

Steps to reproduce:

1. Configure a Zabbix Server with database failover (e.g. PostgreSQL primary/replica).
2. Start the server and ensure all internal processes are running.
3. Trigger a database node switch.
4. Observe server logs during and after the failover.

Result:

• Some internal processes log "database connection re-established" after reconnection.
• Other processes reconnect successfully but do not log this message.
• All processes may log PGRES_FATAL_ERROR originating from the previous database node.

Expected: Logging of successful database reconnection should be consistent across all internal server processes. If a process logs a database connection error related to a lost connection and then successfully reconnects to another database node, the successful reconnection should be logged in