"Ed L." <pgsql@bluepolka.net> writes:
> I'm seeing the following error in 7.4.6. It first surfaced
> after remounting a SAN mount from one box to another and
> then running 'vacuum full':
> pg_dump: ERROR: xlog flush request 68/7D853080 is not satisfied --- flushed only to 0/15A90A8
> CONTEXT: writing block 34 of relation 17156/1470533
What this looks like to me is corrupt data in a page's LSN field (the
first 8 bytes of the page). The LSN is evidently far larger than it
should be. You might try dumping out the indicated page with
pg_filedump (or even just dd/od) to see if anything obvious jumps out.
regards, tom lane