On Tue, 2007-10-23 at 13:58 +0200, Marc Schablewski wrote: > We had some corrupted data files in the past (missing clog, see > http://archives.postgresql.org/pgsql-bugs/2007-07/msg00124.php) and are > thinking about setting up a warm standby system using WAL replication. > > Would an error like the one we had appear in WAL and would it be > replicated too? Or is there some kind of consistency check, that > prevents broken WAL from being restored? Each WAL record is CRC checked, so it is quite unlikely that it could be corrupt on its own. The contents of the WAL record may cause the system to do something wrong on the second server, but if this occurs it usually causes some form of error and we can see that this has happened, report the bug and then restart replication. If that kind of error occurs it is because of a problem in the PostgreSQL software, not a fault of the replication technique. That means these incidents are very rare and we have quickly fixed such bugs when they do occur. I think this has happened twice in 12-18 months. -- Simon Riggs 2ndQuadrant http://www.2ndQuadrant.com ---------------------------(end of broadcast)--------------------------- TIP 1: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to majordomo@xxxxxxxxxxxxxx so that your message can get through to the mailing list cleanly
