Re: Updated version of pg_receivexlog

On Mon, Jun 4, 2012 at 11:25 PM, Ants Aasma <ants(at)cybertec(dot)at> wrote:
> On Thu, Sep 29, 2011 at 11:30 PM, Magnus Hagander <magnus(at)hagander(dot)net> wrote:
>>> it doesn't say that is not possible to use this for a standby
>>> server... probably that's why i get the error i put a recovery.conf
>>> after pg_basebackup finished... maybe we can say that  more loudly?
>>
>> The idea is, if you use it with -x (or --xlog), it's for taking a
>> backup/clone, *not* for replication.
>>
>> If you use it without -x, then you can use it as the start of a
>> replica, by adding a recovery.conf.
>>
>> But you can't do both at once, that will confuse it.
>
> I stumbled upon this again today. There's nothing in the docs that
> would even hint that using -x shouldn't work to create a replica. Why
> does it get confused and can we (easily) make it not get confused? At
> the very least it needs a big fat warning in documentation for the -x
> option that the resulting backup might not be usable as a standby.

Unless I'm missing something, you can use pg_basebackup -x for the
standby. If lots of WAL files are generated in the master after
pg_basebackup -x ends and before you start the standby instance,
you may get the following error. In this case, you need to consult with
archived WAL files even though you specified -x option in pg_basebackup.

> FATAL: could not receive data from WAL stream: FATAL: requested WAL
> segment 00000001000000000000005C has already been removed

Though we have the above problem, pg_basebackup -x is usable for
the standby, I think.

Regards,

--
Fujii Masao