"Simon@2ndquadrant.com" <simon@2ndquadrant.com> writes:
>> Tom Lane wrote:
>> Right, also an area that needs thought. Some other people opined that
>> they want the switchover to occur only on manual command. I'd go with
>> that too if you have anything close to 24x7 availability of admins.
>> If you *must* have automatic switchover, what's the safest criterion?
>> Dunno, but let's think ...
> That's fairly straightforward.
> You use a recovery_command that sleeps when it discovers a full log file
> isn't available - i.e. it has requested the "last" or master-current WAL
> file. The program wakes when the decision/operator command to switchover is
> taken.
But you're glossing over the hard part, which is how to take that
decision (assuming that for some reason you can't afford to wait for
a human to make it).
regards, tom lane