On Tue, Apr 05, 2011 at 12:28:02AM +0200, Ondřej Surý wrote: > > I really, really wanted to have BDB able to handle in-place upgrades > > as well, but I haven't been able to figure out a way. There is an > > ->upgrade method on databases, but it says it's destructive and can > > fail - so you can't just run it during the startup process and hope... > > unless you take a backup first! > > > > Eventually my goal is that you can change the DB type in imapd.conf > > and restart Cyrus, and it will just work. We're nearly there - it > > will automatically convert between types (by reading the magic from > > the top of the file) - but it just can't upgrade BDB. Answer that > > question, and I can give you a 2.4.x release that upgrades magically! > > What if you add an option to cyrus-imapd (to all BDB users) which > would say it can do the in place upgrade. The DB_ENV->upgrade looks > like it is OK, the only problem is that you need to have backups - and > that something which can be done either by maintainer script in > postinst or by administrator - it would also help if there was a > program which could list all the databases which needs to be > converted/backuped. > > If there was a such option I could easily accomplish some magick with > depending on dbX.Y-util (where X.Y is the old version of BDB) and > backup the old database and only after the backup is done (or the > users say "no" to a backup question because he has the backups already > or he doesn't care) I could run the cyrus-imapd --do-upgrade (or > cyrmaster --do-upgrade). That would satisfy both - the safety of the > databases and the need for seamless upgrade. > > How does that sounds?
Fantastic :) Have a look at the "magic" inside ctl_cyrusdb. One option (since we default to all non-bdb now) would be to always take a backup first if it's a BDB file. Then try the upgrade of the backup file, and if THAT works, then create a new skiplist or BDB file in the target place. Make startup a bit slow if you insist on using BDB of course. Bron.
