Re: file system level backup

On 01/06/2014 07:03 AM, zach cruise wrote:
> I am not sure if you have already answered it and I have somehow missed it:
> - Are these 'a' and 'b' on two different servers? ( I think they are on
> different servers)
>
> > yes
>
> - Did you stop the server on 'b' before you replaced the files and
> attempted a startup?
>
> > yes
>
> > thanks. it doesn't help. i also tried pg_ctl without luck
> (http://www.postgresql.org/docs/9.3/static/app-pg-ctl.html)
>
> What exact pg_ctl command you used?
>
> > "pg_ctl start" and "pg_ctl stop"
>
> ---
>
> So is there anything in the Windows system logs?
>
> > looks like file system level backups don't work well on windows
> because they get corrupted during transfer.
>
> Whoa, how did we get to that conclusion?
>
> > as a safety, i had also renamed old data-b. when copying old data-b
> from the network didn't work, i renamed it back. and that worked.
>
> Well all that proves is that there is some difference between the data
> directories. That could be corruption, it could be something else.
>
> Since we are on the subject of corruption and this is Windows, do you
> have anti-virus software running on these machines?
>
> If so, is it pointed at the directories in question?
>
> > yes (symantec) but it is pointed to both directories, old data-b and
> renamed old data-b, so i doubt if that is the issue.

I should have been clearer, I was thinking of the data directories on
both a and b machines. In any case anti-virus software corruption of
files in data directories is a known issue. Feel free to search the
archives for the reports:) Whether it happens depends on how active and
aggressive the a/v software is.

I am leaning to the idea that when you did the original copy of data
directories from a and b the respective servers where not completely
shut down. You mentioned that pgBouncer was running when you did the
copying. It could be it was holding connections open to the servers that
left them running. At present you say the a server is running. As a test
I would suggest shutting it down(and verifying it is not running) do a
copy to b and try again to start the b server.

>

--
Adrian Klaver
adrian(dot)klaver(at)gmail(dot)com