Hi, Just want to let everybody knows
So, I found out this morning what went wrong. For some reason, there were some bad wal log files in pg_xlog. I believe that they got generated during the backup last Monday, but I don't know why. I speculate that may be the wal_keep_segments was not set high enough as I have changed it recently. Luckily, I have archived the wal log files. And by comparing between the two directories, I did see those bad wal log files in pg_xlog directory only. Yes, we were looking at Barman before. But at that time Barman didn't support our version of PostgreSQL. I think that I will pursue this. Thanks again. On Fri, Sep 18, 2015 at 2:40 PM, David Steele <da...@pgmasters.net> wrote: > On 9/18/15 3:44 PM, Michael Chau wrote: > >> Hi Jeff, >> >> Only if you are very lucky. If your tar command tars up the pg_xlog >>> directory as the last thing it does, then you are probably going to be OK. >>> Otherwise, it is a crap shoot. >>> >> >> May be that's it. I have another similar set up, but the pg_xlog is a >> soft link to another directory, and I use 'tar -chvzf'. It tar up the >> pg_xlog at the very last. And the restore is fine. >> > > This is still not always safe. It depends on your wal_keep_segments > settings and some luck. WAL segments can be recycled during the backup. > > For this one, DB1 and DB2, the pg_xlog is the directory itself, and I >> use 'tar -cvzf'. And it tar up pg_xlog at the beginning. I always have >> doubt about it. But I though pg_stop_backup() and pg_start_backup() like >> freezing would prevent the inconsistency. >> > > This is definitely not a good idea. > > Indeed, I will look inot pgbasebackup. >> > > pg_basebackup is good for creating replicas but for real backup you might > want to consider purpose-built backup software like pgBackRest or barman. > > -- > -David > da...@pgmasters.net > -- *Michael Chau* *Database Administrator* *GAME GOLF* 77 Geary St, 5th floor San Francisco, CA 94108 c) *510-366-3800* e) *michael.c...@gameyourgame.com <http://gameyourgame.com>* f) www.facebook.com/gamegolf <http://www.facebook.com/gamegolf.gyg> t) @GAMEGOLF w) www.gamegolf.c <http://www.gameyourgame.com/>*om*
