Re: Error in starting PostgreSQL Server 7.4 after crash

sagar koirala <sagarkoirala25(at)hotmail(dot)com> writes:
> So, I used pg_resetxlog PGDATA with PGDATA pointing to my current /pgsql/data. It said transaction log reset. At this point, the postgresql is not running, so I cannot dump my old data. Starting the postgresql doesn't work.

> So I tried: export PGDATA=/var/lib/pgsql/data
> Then I tried to pg_ctl start but ended up with following message:

> -bash-3.00$ pg_ctl start
> FATAL: database files are incompatible with server
> DETAIL: The database cluster was initialized with BLCKSZ 6330300, but the server was compiled with BLCKSZ 8192.
> HINT: It looks like you need to recompile or initdb.

Seems like you must have used a pg_resetxlog that doesn't actually match
your database. You omitted all the details of "installed postgres 7.4
again" but I'll bet you messed up there somehow. (32-bit vs 64-bit is
one possible gotcha that I don't think 7.4 defended against very well.)

> Any suggestions? Thanks in advance.

Get the right software version and start over from the data-directory
backup that I hope you still have. The data directory you have now is
likely unsalvageable --- just running pg_resetxlog again is unlikely
to fix it.

Worst case, you'll have to initdb and start from the latest pg_dump
dump you've got ...

regards, tom lane