On Tue, Jul 21, 2015 at 5:12 PM, Joshua D. Drake <j...@commandprompt.com> wrote: > > > "When backend node status changes by failover etc., watchdog notifies the > information to other pgpool-IIs and synchronizes them. When online recovery > occurs, watchdog restricts client connections to other pgpool-IIs for > avoiding inconsistency between backends."
You're taking that out of context, though. That is coming from the doc http://www.pgpool.net/docs/latest/pgpool-en.html#watchdog, which is describing how Watchdog coordinates fault of *pgpool-II* backend processes and coordinates the pgpool-II instances with each other. It is for maintaining availability of pgpool-II and monitoring for failure of pgpool-II backends, not Postgres/postmaster. *Will J. Dunn* *willjdunn.com <http://willjdunn.com>* On Tue, Jul 21, 2015 at 5:12 PM, Joshua D. Drake <j...@commandprompt.com> wrote: > > On 07/21/2015 01:37 PM, William Dunn wrote: > >> But it appears that the fail condition for "watchdog" is the failure of >> a pgpool-II instance. In the configuration described in the wiki you >> would put a pgpool-II instance on each Postgres node, and if one of the >> pgpool-II instances fails it executes a script (which can create the >> trigger file to promote the standby to master). However, if the fail >> condition for watchdog is a failure of the pgpool-II instance what >> happens if the DBMS has availability issues but the pgpool-II process on >> that server is ok? The fail condition would never be triggered, right? >> > > What I am going off of is: > > "When backend node status changes by failover etc., watchdog notifies the > information to other pgpool-IIs and synchronizes them. When online recovery > occurs, watchdog restricts client connections to other pgpool-IIs for > avoiding inconsistency between backends." > > A backend node status would change if say the master went down, at that > point pgpool can be instructed either automatically or manually to failover > (depending on configuration) and allow the slave to failover. > > Sincerely, > > > JD > > -- > Command Prompt, Inc. - http://www.commandprompt.com/ 503-667-4564 > PostgreSQL Centered full stack support, consulting and development. > Announcing "I'm offended" is basically telling the world you can't > control your own emotions, so everyone else should do it for you. >
