Hi Ragnar! We are currently doing exactly that. Interesting enough, starting off the same software version 2.1.18. IMO this is a very nice and very smart way to migrate, especially if the total number and size of your mailboxes doesn't make it easy to just "qickly" copy everything over to a new box. Also I guess you're aware that some of the internals changed between Cyrus 2.1 and 2.2, so you cannot do a plugin replacement. Cyrus 2.2 or 2.3 will just not read your stored mailboxes from 2.1 without some (irreversible) upgrades of the data. Maybe it would be worth to create a page on the Cyrus wiki for just that subject. I think you and us are not the first people to work on exactly this. And there are some gotchas. Unfortunately, once people mastered the task, they seldom come back to do some documentation and share their experience. One gotcha I can save you: If you have made your setup, i.e. after you will have an aggregator and what's your one and only mailserver today will be just one of multiple backends, you will possibly want to move mailboxes off the backend which is running 2.1.18 to some 2.3.x backend. You will find your Sieve scripts to be not working anymore. This is *not* because they are not migrated when you move a mailbox. But it's because on newer versions of the sieve daemon, you need to compile them to bytecode and this isn't done on the fly by the mailbox rename (move) process. The other problem you may or you may not have: https://bugzilla.andrew.cmu.edu/show_bug.cgi?id=3213 Unfortunately this bug is not getting a lot of attention; some previous questions about this on this mailing list neither. So we digged a bit deeper into the issue and I would be more then interested to hear if you run into that problem as well or not. Basically, AFAIK, the communication between a Murder frontend and a backend is IMAP. It's not secret proprietary Cyrus internal protocol. The gurus here may correct me, but I thin theoretically, a backend doesn't even have to be a Cyrus IMAPd. (Would be fun to try and run for example an MS Exchange server as a backend in a Murder cluster.) The only thing I *think* you'd need to use an arbitrary IMAP server as a backend would be to make sure you find a way to tell the mupdate master that mailbox XYZ is on a server a with credentials b and that the backend server supports proxy authentication. But I am just speculating here. But on that background, the version number of your backends really shouldn't make any difference. Regarding the above mentioned ticket, we have in the meanwhile made some more tests and added a new, fresh 2.1.18 backend to our Murder. And voila; we can *not* reproduce the problem. So it may be something in the config ouf our old 2.1.18 machine which is causing this behaviour we see, i.e. occasional "Server(s) unavailable to complete operation" error messages which seem to be a race condition at first. I'll keep you posted, but at the same time, I'd also be interested in your findings. But me personally, I can only encourage you to go for what you have in mind. Unless you have a very tight deadline and very little data to migrate. Regards, Torsten Ragnar Sundblad schrieb: > Is murder/aggregator backwards compatible with older imap > servers? > > We want to migrate form a single 2.1.18 cyrus imap server to > multiple 2.3.x servers. An idea is to insert a common > murder/aggregator in front of both the 2.1.18 server and the > new servers, and seamlessly migrate users. Would this be > doable? > > Thanks! > > /ragge > > ---- > Cyrus Home Page: http://cyrusimap.web.cmu.edu/ > Cyrus Wiki/FAQ: http://cyrusimap.web.cmu.edu/twiki > List Archives/Info: http://asg.web.cmu.edu/cyrus/mailing-list.html ---- Cyrus Home Page: http://cyrusimap.web.cmu.edu/ Cyrus Wiki/FAQ: http://cyrusimap.web.cmu.edu/twiki List Archives/Info: http://asg.web.cmu.edu/cyrus/mailing-list.html
