Re: pg_basebackup creates a corrupt file for pg_stat_tmp and pg_replslot on a backup location

On 4/14/16 2:55 PM, Robert Haas wrote:
> On Thu, Apr 14, 2016 at 11:12 AM, Andres Freund <andres(at)anarazel(dot)de> wrote:
>> On 2016-04-14 13:43:34 +0530, Ashutosh Sharma wrote:
>>> I tried performing pg_basebackup after creating a symbolic link for
>>> pg_replslot, pg_stat_tmp, pg_log and pg_clog in the source directory
>>
>> That's not supported, and I strongly suspect that you're goint to hit
>> more than just this issue. The only directory you're allowed to symlink
>> away is pg_xlog.
>
> I think various tools might choke on such a configuration, but I'm not
> entirely sure why we haven't made them all work. Is there some more
> fundamental problem?

I'm don't think there's a fundamental problem it just takes a lot of
work to get it right. Extensive link support has been added for
pgBackRest 1.0 and it took a lot of effort, not just for the backup
itself (loop detection, links into multiple hierarchy levels, etc.) but
adding options to the restore to make remapping possible on systems with
different disk layouts.

--
-David
david(at)pgmasters(dot)net