[pgpool-general: 8839] Re: What criteria is for a `failover` and what for a `recovery`?

[Bo Peng]

Hi,

> Suppose I have configured ` health_check_user` , health_check_password,
> health_check_database & health_check_max_retries
> 
> Suppose now no postgres server is up. Will starting a pgpool automatically
> detect the flaw and execute the failover script, even if it yields no
> result?

Yes. Failover will be performed and pgpool will not accept any requests.
Before starting pgpool, we need to make sure one primary is available.
 
> About `recovery` same thing again. Will the postgres server starts itself
> before  pgpool recognize it as a `recovery node`? In this case, should
> pgpool stop this new server before starting the replication?
> 
> In general, how do you define the trigger event for each?

Pgpool-II's "online recovery" is used to recovery a failed (DOWN) standby node.
Pgpool-II's "online recovery" performs the recovery scripts which will automatically
configure streaming replication.

The following documents may help you configure pgpool.

https://www.pgpool.net/docs/latest/en/html/example-cluster.html
https://www.pgpool.net/docs/latest/en/html/example-replication-mode.html
-- 
Bo Peng <pengbo at sraoss.co.jp>
SRA OSS LLC
TEL: 03-5979-2701 FAX: 03-5979-2702
URL: https://www.sraoss.co.jp/