Re: FATAL 2: (pg_clog ... no such file or directory)

kaolin fire <cognosco(at)tentacle(dot)net> writes:
> Where would I go to start tracking down recurring error messages of the
> sort:

> FATAL 2: open of /usr/local/pgsql/data/pg_clog/06F7 failed: No such
> file or directory
> FATAL 2: open of /usr/local/pgsql/data/pg_clog/0707 failed: No such
> file or directory

> 06F7 and 0707 do not exist. Currently just looks like it goes from
> 0000 (May 14 2002) to 004F (Feb 6 2004, and counting).

Given those facts, you have corrupt data --- specifically, a wildly
out-of-range transaction number in some tuple header, causing the tuple
validity checker to try to fetch a nonexistent page of the CLOG. The
odds are good that the corruption extends further than just the one
field; that just happens to be the one that gets checked first.

There are discussions in the mailing list archives about how to locate
and clean up corrupted data. It's a pretty messy process but you can
usually get back everything except the rows on the particular corrupted
page (I'm optimistically assuming there's only one). Looking for
threads mentioning pg_filedump might be the quickest way to find info.

regards, tom lane