"Benjamin Arai, Ph.D." <benjamin(at)araisoft(dot)com> writes:
> The server is still running but pg_dumps output the following error. What
> should I do?
Try reindexing pg_index in whichever database is giving trouble.
Depending on what PG version you are using (which is something that
should ALWAYS be mentioned in any kind of trouble report), you might
need to stop the server so you can do this in a standalone backend.
Read the relevant version of the REINDEX reference page for more info.
regards, tom lane