Tony Nelson wrote: > This morning my server (ubuntu 10.04 LTS, pg 8.4 from apt) > experienced a disk corruption which caused errors like this: > > Feb 18 08:50:07 ihdb1 postgres[13317]: [2-1] > user=postgres,db=instihire ERROR: invalid page header in block 10 > of relation base/16384/8082305 Do you know why? If not, that machine is not to be trusted. > I am ok, because I have a dump from last night, and wal since then. That dump was taken according to PITR instructions, not from pg_dump or pg_dumpall, I hope. > As a test, I tried doing a dump like this from the broken server: > > pg_dump -Fc mydb > busted.dump > > I restored this dump on a test server, and all of the data looks > ok, and my application is able to run the operation that was > failing in production just fine. > > My question is simple, is my dump good? Maybe; maybe not. I would try to restore from that dump you mentioned, run pg_dump on that, and compare the two files which came out of pg_dump. Or just use the dump if you can restore it and you're sure it's up to date. > Is it possible that pg_dump was able to correctly save the data > that "select .. " and "update.. " couldn't. pg_dump essentially just does a SELECT from each table. If the corrupted relation was an index, you might have dodged the problem mentioned above, but if a page in that index got corrupted, why assume damage was localized to that one place? You really have two problems to address here: how best to recover your data, and how to prevent a recurrence. What version of PostgreSQL is this exactly? (It's best to SELECT version(); and copy/paste the results.) -Kevin -- Sent via pgsql-admin mailing list (pgsql-admin@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin
