Tom Lane wrote:
Darren Reed <darrenr+postgres@xxxxxxxxxxxx> writes:
> Starting up postgres, I get the log contents below.
> Is it really as bad as it suggests, namely that I
> need to recover from backup?
Probably :-(
I've started a new db in parallel with the old data and I'm rebuilding,
and if I can rebuild quicker than I can recover old data, I'll do that.
pg_resetxlog would let you into the database, but I do not have high
hopes about the consistency/correctness of what you'll find. The best
advice would be:
1. pg_resetxlog
# su postgres -c "/usr/pkg/bin/pg_resetxlog -n /data/db"
pg_control values:
pg_control version number: 812
Catalog version number: 200510211
Database system identifier: 5138205682483264479
Current log file ID: 2
Next log file segment: 103
Latest checkpoint's TimeLineID: 1
Latest checkpoint's NextXID: 4570963
Latest checkpoint's NextOID: 24576
Latest checkpoint's NextMultiXactId: 1
Latest checkpoint's NextMultiOffset: 0
Maximum data alignment: 4
Database block size: 8192
Blocks per segment of large relation: 131072
Maximum length of identifiers: 64
Maximum columns in an index: 32
Date/time type storage: floating-point numbers
Maximum length of locale name: 128
LC_COLLATE: C
LC_CTYPE: C
# su postgres -c "/usr/pkg/bin/pg_resetxlog -f /data/db"
Transaction log reset
And a start is greated with:
LOG: database system was shut down at 2008-02-20 11:04:51 PST
LOG: checkpoint record is at 2/6A00001C
LOG: redo record is at 2/6A00001C; undo record is at 2/6A00001C;
shutdown TRUE
LOG: next transaction ID: 4570963; next OID: 24576
LOG: next MultiXactId: 1; next MultiXactOffset: 0
PANIC: could not access status of transaction 4570963
DETAIL: could not read from file "pg_clog/0004" at offset 90112:
Undefined error: 0
LOG: startup process (PID 29662) was terminated by signal 6
LOG: aborting startup due to startup process failure
2. pg_dumpall
3. initdb, restore from backup
4. compare dump from step 2 to backup dump, apply any changes that seem
sane
And don't forget
5. Figure out why a simple power failure was able to do this to you,
and fix it. The most likely bet is that your disk drives are lying
about write completion ... see the PG archives for discussion.
Yes, that I can believe.
Darren
---------------------------(end of broadcast)---------------------------
TIP 3: Have you checked our extensive FAQ?
http://www.postgresql.org/docs/faq
