Обсуждение: Online backups and WAL

Hi,

I'm currently testing online backups, and I'm facing the problem of a missing
WAL when I do the backup : the current WAL isn't archived when I save the
archives, and is required to recover...
I've read in the mailing list archives that it can be solved by copying the
current WAL from pg_xlog. Even if this solution works, it looks to me to be
more of a workaround than anything else, and adds some complexity to an
operation that is allready not that simple.
I'd like to know if there is a way to force the switch from a WAL to the next
one, like with an 'alter system archive log current' in Oracle.

Cheers.

Marc Cousin

Marc Cousin wrote:
> Hi,
>
> I'm currently testing online backups, and I'm facing the problem of a missing
> WAL when I do the backup : the current WAL isn't archived when I save the
> archives, and is required to recover...
> I've read in the mailing list archives that it can be solved by copying the
> current WAL from pg_xlog. Even if this solution works, it looks to me to be
> more of a workaround than anything else, and adds some complexity to an
> operation that is allready not that simple.
> I'd like to know if there is a way to force the switch from a WAL to the next
> one, like with an 'alter system archive log current' in Oracle.

No, there is no way to force a switch.  It is on our TODO list as
something to fix for 8.1.

The development version of the docs make it much clearer:

    http://candle.pha.pa.us/main/writings/pgsql/sgml/backup-online.html

This documentation update will be in 8.0.X.  Sorry the system is
currently confusing.

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