Re: Setting up HA postgresql

On 07/21/2015 07:07 PM, Tatsuo Ishii 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?
>
> No. The condition (PostgreSQL failure) will be detected by one of
> pgpool-II (not watchdog process) and the pgpool-II will disconnect the
> failed PostgreSQL, then execute failover script (if defined) which
> will usually promote standby PostgreSQL (if failed PostgreSQL was
> primary) or just ignore the broken PostgreSQL if it was standby.

Thank you Tatsuo, I was having trouble explaining.

Sincerely,

JD

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