Re: Power outage borked things (8.1.10)...

Hannes Dorbath wrote:
> Michael Monnerie wrote:
> > On Mittwoch, 20. Februar 2008 Tom Lane wrote:
> >> 5. Figure out why a simple power failure was able to do this to you,
> >> and fix it. The most likely bet is that your disk drives are lying
> >> about write completion ... see the PG archives for discussion.
> >
> > It could be a caching RAID controller without battery backup unit.
> > Nothing help you in a power failure then, except a good backup.
> > Had this with a customer - no more filesystem after reboot...
>
> I hardly understand why such things still happen today. It's one of the
> most important admin tasks to make sure fsync / fua behave as they should.
>
> Wouldn't it be a good idea to add a chapter to the installation docs?
>
> They cover SHM settings and vm.overcommit -- why not a short
> introduction to fsync, write caches, write barriers and a few examples
> of sane and problematic setups as well as links to tools to verify a setup?

We have a new section added in 8.3 for exactly that:

http://www.postgresql.org/docs/8.3/static/wal-reliability.html

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://postgres.enterprisedb.com

+ If your life is a hard drive, Christ can be your backup. +