Re: pg_start_backup: file has vanished from pg_subtrans/

Op 08/08/2015 om 14:24:00 -0400, schreef David Steele:
> On 8/7/15 7:01 AM, Leo Baltus wrote:
> >While backing up some postgresql-8.4.2 instances using
> >pg_start_backup()/pg_stop_backup()
> >
> >We noticed that sometimes rsync complains:
> >
> >file has vanished: "............./data/pg_subtrans/3A37"
> >rsync warning: some files vanished before they could be transferred (code 24) at main.c(1039) [sender=3.0.6
>
> It's perfectly normal for Postgres to remove files during a backup. If a
> table is dropped then the files storing that table will be deleted. Files
> can also be removed from pg_subtrans once they are no longer needed.
>
> >We already have excluded pgsql_tmp/ pg_xlog/ and pg_stat_tmp/ so I was
> >tempted to exclude pg_subtrans/ as well. However some googling seems to
> >suggest that this might invalidate the backup:
>
> I would recommend only excluding pg_xlog as recommended in the Postgres
> docs.
>

Check.

> >https://groups.google.com/forum/#!msg/pgbarman/zQxg6pOXkZ8/AmTmVtUA3dEJ
> >
> >I am not sure what to believe, either
> > - my backup was invalid and I have to take measures to prevent this
> > (and file a bug report)
>
> Your backup should be good so long as you've captured all the WAL.
>
> > - I can ignore this *and* can safely exclude pg_trans/ from my backups.
> > - there is some other workaround...
>
> Do *not* exclude pg_subtrans.

Ok, for now I will ignore rsync's exit code 24.

>
> You may also want to look at backup software such as pgBackRest. It
> understands that files can be removed during backup and does not emit
> warnings when it happens (though info messages are still logged depending on
> your log level).

Thanks!

--
Leo Baltus