On 03/19/2014 10:28 AM, Kyotaro HORIGUCHI wrote:
> The*problematic* operation sequence I saw was performed by
> pgsql-RA/Pacemaker. It stops a server already with immediate mode
> and starts the Master as a Standby at first, then
> promote. Focusing on this situation, there would be reasonable to
> reset backup positions.
Well, that's scary. I would suggest doing a fast shutdown instead. But
if you really want to do an immediate shutdown, you should delete the
backup_label file after the shutdown
When restarting after immediate shutdown and a backup_label file is
present, the system doesn't know if the system crashed during a backup,
and it needs to perform crash recovery, or if you're trying restore from
a backup. It makes a compromise, and starts recovery from the checkpoint
given in the backup_label, as if it was restoring from a backup, but if
it doesn't see a backup-end WAL record, it just starts up anyway (which
would be wrong if you are indeed restoring from a backup). But if you
create a recovery.conf file, that indicates that you are definitely
restoring from a backup, so it's more strict and insists that the
backup-end record must be replayed.
> 9.4 canceles backup mode even on
> immediate shutdown so the operation causes no problem, but 9.3
> and before are doesn't.
Hmm, I don't think we've changed that behavior in 9.4.
- Heikki