On Saturday 24 June 2006 00:01, Wesley Craig wrote: > If you're concerned that the databases files be consistent, then the > only way is to cleanly shutdown the processes that have the databases > open. Snapshots will definitely NOT guarantee consistency of the > databases, since consistent database updates can take multiple > writes. Take for example the recent discussion of database > corruption during sudden power lose. Snapshots stop user process > file access very suddenly, not cleanly. Problems created by > snapshots can usually be corrected with reconstruct. Hmm what a pain. I would have thought that the on disk format would be self consistent :( > The real question is, what are your backups for? If you're concerned > about recovering mail that the user has deleted, then rsync-ing the > live system is fine. If you want a consistent copy that you could > switch to in the event of a large-scale disaster, then you probably > want to explore application-level replication. If the database is not consistent then the seen flags will be broken.. This was the primary complaint of my users last time I had to do a large scale restoration (after disk failure). -- Daniel O'Connor software and network engineer for Genesis Software - http://www.gsoft.com.au "The nice thing about standards is that there are so many of them to choose from." -- Andrew Tanenbaum GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C
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