Re: bad block problem

On 12/08/2011 07:41 AM, Kevin Grittner wrote:

> That sounds like your storage system is failing, quite independently
> from PostgreSQL.  Copy the entire data directory tree to some other
> medium immediately, and preserve this copy.  If you hit bad blocks,
> retry if possible.

If you find files you can't copy in their entirety, try using dd_rescue
to copy it with a hole for the bad block. dd_rescue is an _incredibly_
useful tool for this, as it'll do bad-block-tolerant copies quickly and
efficiently.

Once you have a complete copy of your datadir, stop working on the
faulty machine. Make your first copy read-only. Duplicate the copy and
work on the duplicate when trying to restore. I'd start with enabling
zero_damaged_pages to see if you can get a dump that way.

Do **NOT** enable zero_damaged_pages on the original. Do it on the
duplicate of the copied data.

--
Craig Ringer