On Thu, Jun 17, 2010 at 4:39 AM, Felde Norbert <fenor77@gmail.com> wrote:
> I use 8.2 on a windows server 2008.
> Suddenly postgres crashed and I can not do anything.
> Strange things happend to postgres in the last few weeks. Once, there
> was so many postgres process, that I could not connect to it with
> pgAdmin3. It said that too many connections and I had to restart
> postgres. Than, after a while the postgres service stopped but some
> process ran and it was still accsessable so the application which used
> it ran without any problem and I could simply start postgres again.
>
> Now something is wrong, I can not make backup and the vacuum stops too.
> The message is
> pg_dump: Error message from server: ERROR: could not access status of
> transaction 3974799
> DETAIL: Could not read from file "pg_clog/0003" at offset 204800: No error.
> pg_dump: The command was: COPY public.active_sessions_split (ct_sid,
> ct_name, ct_pos, ct_val, ct_changed) TO stdout;
> pg_dump: *** aborted because of error
>
> The only one thing I found to correct this is to create a file filled
> with binary 0 and replace clog/0003. Both files size was the same but
> I get that errormessage again.
>
> I tried even with a bigger empty clog/0003 file but than I get that:
> pg_dump: Error message from server: ERROR: xlog flush request
> 0/A19F5BF8 is not satisfied --- flushed only to 0/A02A1AC8
> CONTEXT: writing block 1149 of relation 1663/4192208/4192508
> pg_dump: The command was: COPY public.history (historyid, adatkod,
> elemid, userid, ido, actionid, targyid, szuloid, opvalue, longfield,
> longtext) TO stdout;
> pg_dump: *** aborted because of error
>
> I tried to drop the last few transaction with pg_resetxlog and hoped
> to save some data but there is again the original error message.
>
> I checked the permissions of the whole data dir. The owner of it is
> postgres and has full permission.
>
>
> Can anyone suggest something?
> Many data would be lost if I can not repaire that so please!
First, I'd suggest you make a copy of the database before you do anything else.
Second, is it possible your disk filled up at some point during all of this?
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise Postgres Company