Wim>> I have a postgres db version 8.2.15 (Yes, I know it's rather old version). Wim>> After correcting some disk and file system problems the postgres table seems to be corrupt, returning: Wim>> Wim>> ERROR: xlog flush request B67/44479CB8 is not satisfied --- flushed only to B67/429EB150 Wim>> CONTEXT: writing block 33652 of relation 1663/18776/21757 Wim>> Wim>> on a simple select statement. Wim>> What is the best way to get past this? Tom> Well, *first*, stop the database and take a filesystem-level backup of Tom> the $PGDATA directory tree. That will at least let you get back to Tom> where you are now if experimentation makes it worse. Tom> You could suppress this particular class of complaints by using Tom> pg_resetxlog to advance the WAL endpoint past whatever's in the Tom> database. That won't do anything to fix corruption, it'll just Tom> silence this particular consistency check. But it might be Tom> enough to let you run pg_dump. Thx for the quick answer. Copy of PGDATA directory was already taken After studying http://www.postgresql.org/docs/8.2/static/app-pgresetxlog.html I ran: su <db-user> -c 'pg_resetxlog -f -x 0x9A00000 -m 0x10000 -O 0x10000 -l 0x1,0xB67,0x58 <PGDATA-directory>' and yes, it worked perfectly! After that I could pg_dump, drop database, create database and import the dump. Now, I'm verifying the consistency on the level of my application. Thx, again, Tom. For other people, looking for info about recovering postgresql DBs: I first did: su <db-user> -c 'pg_resetxlog -n <PGDATA-directory>' That returned: Current log file ID: 2919 (= 0xB67) Next log file segment: 67 (= 0x43) Latest checkpoint's TimeLineID: 1 (= 0x1) Latest checkpoint's NextXID: 0/161392765 -> (= 0x99EA87D) Latest checkpoint's NextOID: 136502229 Latest checkpoint's NextMultiXactId: 4129 (= 0x1021) Latest checkpoint's NextMultiOffset: 16888 (= 0x41F8) Then I checked $PGDATA/pg_xlog/ -> 'highest' filename: 0000000100000B6700000057 $PGDATA/pg_clog/ -> 'highest' filename: 0099 $PGDATA/pg_multixact/offsets/ -> 'highest' filename: 0000 $PGDATA/pg_multixact/members/ -> 'highest' filename: 0000 No more magic needed, then what is under: http://www.postgresql.org/docs/8.2/static/app-pgresetxlog.html For completeness: next I did: pg_dump -U <db-user> <my-db-name> >dump.sql psql -U <db-user> template0 -c "drop database <my-db-name>" psql -U <db-user> template0 -c "create database <my-db-name>" psql -U <db-user> <my-db-name> -c -f dump.sql -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
