Re: server crash, need to restore DB functionality

On Tue, Apr 29, 2008 at 11:18 AM, e t <albunix(at)gmail(dot)com> wrote:
> Hello,
>
> we run
>
> 7.4.7
>
> on a Redhat RHEL server.

Two points.
1: The 7.4.x series is pretty old. You should consider upgrading to a
newer version when you have time. 8.3.1 is stable but a little new.
8.2.7 is very stable and much faster than 7.4.
2: 7.4 series is up to 7.4.19. You may be missing 3 years of updates,
unless you are using RedHat's version and they are back porting fixes
to 7.4.7. I didn't think they did that, but Tom Lane would be a good
person to ask about that.

> Today that was a severe server crash and NOC seems to have repeatedly
> attempted a reboot without properly unmounting the file systems.

The machine that gives them a banana when they push a button probably
wasn't working quite right :)

> I am getting errors such as the following
>
> Apr 29 13:15:34 cp postgres[4961]: [106-1] ERROR: could not open relation
> "users_pkey": Permission denied
> Apr 29 13:15:34 cp postgres[4961]: [107-1] ERROR: could not open relation
> "users_pkey": Permission denied
> Apr 29 13:15:34 cp postgres[4957]: [113-1] ERROR: could not open relation
> "users_pkey": Permission denied
>
> when attempting to have my application connect to the DB
>
> Please let me know what sort of procedure are available to us
> to have such functionality restored.

you should restore from backup if possible.

> We do have backups.

pg_dump backups (good thing) or file system backups (maybe good,
likely not coherent)

> Being it is one day old, are we going to loose information when attempting
> to do a restore?

Well, if you can't connect, then no. OTOH, if you can still connect
and you've been updating data, then yes. you'll lost everything you
had since your last backup.

You may be able to fix things. Trying reindexing the failing table / indexes.