Re: pgpool question

On Thu, 10 Mar 2005, Tatsuo Ishii wrote:

>> I'm experimenting with pgpool 2.51 on my Linux box runnung
>> two postgresql backends: pg74:5432 and pg801:5433
>>
>> I configured pgpool to use pg74:5432 as primary backend and
>> pg801:5433 as second one. Pgpool is running on default port (9999) and
>> I configured my web application to use it, so I could start/stop backends
>> without disturbing client (web browser).
>>
>> When I stop primary backend (pg74:5432) pgpool switched to backend
>>      failover from (5432) to (5433) done
>> but when I start primary and stopped secondary backend pgpool
>> never switched back to primary backend as expected !
>> I see bogus message like:
>>      starting failover from (5433) to (5433)
>>
>> What I'm doing  wrong ?
>
> That's an intended behavior. Or at least a side effect of failover
> design. If we allow unlimited switching between the master and the
> secondary, pgpool could repeat switching forever if we have unliable
> network or hardware.

You may recognize manual action of DBA, that is why '-s m switch' is needed !


>
> However it would be easy to modify pgpool to allow automatic switch
> back (with a risk of unwanted repeating switching, of course). Is
> this what you want?

No, your arguments are important. I don't want too much intelligence, but
when I restart primary backend by hand I don't see any problem to
switch pgpool back using -s m switch (also by hand). For brave, probably,
something like --auto would fine.



> --
> Tatsuo Ishii
>
    Regards,        Oleg
_____________________________________________________________
Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
Sternberg Astronomical Institute, Moscow University (Russia)
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