[pgpool-general: 9426] Re: detach node causes psql to hang until pgpool is restarted

[Tatsuo Ishii]

> All;
> 
> 
> I setup pgpool and it is working well per load balancing and queries.
> 
> However if I use pcp_detach_node to detach a standby then psql just
> hangs until I restart pgpool

This is an expected behavior if you set:

backend_flag0 = 'DISALLOW_TO_FAILOVER'
backend_flag1 = 'DISALLOW_TO_FAILOVER'
backend_flag2 = 'DISALLOW_TO_FAILOVER'

> after a restart the detached node shows as down
> 
> Is there a way to detach a node without needing to restart pgpool?

Yes, set below:

backend_flag0 = 'ALLOW_TO_FAILOVER'
backend_flag1 = 'ALLOW_TO_FAILOVER'
backend_flag2 = 'ALLOW_TO_FAILOVER'
failover_command = ''

This will allow pgpool to detach a backend node using pcp_detach_node
or failover triggered by health check.  Setting failover_command to ''
will do nothing while detaching node or failover except changing the
backend status ("UP" or "DOWN" etc.) in pgpool.

Best regards,
--
Tatsuo Ishii
SRA OSS K.K.
English: http://www.sraoss.co.jp/index_en/
Japanese:http://www.sraoss.co.jp