[pgpool-general: 8316] Re: Degenerate cluster

[Tatsuo Ishii]

> Is it possible to have pgpool keep running with a single node in the cluster?

>From Pgpool-II 4.3 that is possible. See the manual:
https://www.pgpool.net/docs/latest/en/html/runtime-watchdog-config.html#CONFIG-WATCHDOG-FAILOVER-BEHAVIOR

especially this parameter: wd_remove_shutdown_nodes

> I have 3 nodes in my cluster and I want to upgrade postgresql on them with minimal downtime.
> I figured I would shutdown postgresql and pgpool on 2 of them and leave the 3rd one up until the others are upgraded and ready.
> However when I stopped pgpool on 2 nodes the 3rd node (psql-dev-03) gave up the virtual IP and I have no database connection.
> Is this expected?

Yes, because the quorum is lost.

Best reagards,
--
Tatsuo Ishii
SRA OSS, Inc. Japan
English: http://www.sraoss.co.jp/index_en.php
Japanese:http://www.sraoss.co.jp