On Fri, Mar 12, 2004 at 02:33:33PM +0100, Christoph Nagelreiter wrote: > has anyone experience with the Cyrus IMAP Aggregator > (http://asg.web.cmu.edu/cyrus/ag.html) in an production enviroment > (>50.000 Mailboxes)?
Yes. 70K accounts, last time I checked, in a University environment. > Which hardware do you use? 5 machines : - 2 x frontends: Quad Xeon 2.8, 4GB RAM. These machine also run an MTA and a PHP webmail package (Horde/IMP). - 1 x MUPDATE master server: Dual Xeon, 1 or 2 GB or RAM (don't remember). This machine is also running a highly sollicated MySQL database (Horde preference backend). - 2 x backends: Dual Xeon, 1 or 2 GB or RAM (don't remember) and a 700GB SCSI RAID 5 array locally attached (standard HPaq controller). Of all these machines, only the frontends are right-sized. The rest is *way* overkill. Load avg rarely goes over 5 on the frontend machines and never over 1 on the MUPDATE master or the backend. But hardware is so cheap these day, I see no reason not to be prevoyant and buy good hardware. > Any problems? Yes, a few. We had database corruption problems on the MUPDATE master that caused a lot of downtime recently. We are currently experiencing intermittent segfault on the MUPDATE master that I am investigating. Configuration is a pain. SASL is a complicated beast. The databse backend you choose have very important impact on the stability and performance and they need to be researched in depth before commiting to a choice. If there is one thing I wished I did better with my deployement of Cyrus imapd, it would have been researching database issue and recovery procedure beforehand. The documentation is scattered and lacking on certain aspect (like, for example, database maintenance and recovery) and sometime out-of-date. The developper seem to favor ad-hoc documentation on a WiKi, which I personnally can't wrap my mind around but YMMV. I do not want to sound too negative, though. This deployement have been a rough ride in the past three months, but overall I am relatively satisfied. If it had to be done again, I would stay with Cyrus, but make sure I am prepared better. If I where you, I'll start small. If you have the opportunity to test drive it in production on a smaller scale first (ie, a department with >= 10K accounts), you could start there. This would leave you time to familiarize yourself with the software before commiting fully. On the plus side, you should note that : - It's very flexible - Performance is excellent (beat my expectation by a *large* margin) - Full of features few others IMAP daemon have : ACL, single-instance store, duplicate delivery suppression, folder annotation, etc. - Strict adherence to RFC. - The price is right :) At this point, if you need a high-performance scalable IMAP daemon, Cyrus is the best choice within OSS. You mentionned 50K accounts. I do not know if you are planning a lot of growth, but if you don't you may want to consider not going with a Murder in the first place and opt for a standalone server instead. This would simplify your setup immmensely. You may believe 50K accounts is a lot, but it's really not that big (IIRC, some participant on this list host > 250K accounts). Unless the usage pattern of your users is very hard, you could probably host all your accounts on a single relatively decent machine (quad CPU, >= 4GB RAM and fast disk) if it's being dedicated entirely to Cyrus (no MTA, no webmail, etc). This is, of course, a very rough and uneducated estimate so YMMV. Good luck ! -- Etienne Goyer Linux Québec Technologies Inc. http://www.LinuxQuebec.com [EMAIL PROTECTED] --- Home Page: http://asg.web.cmu.edu/cyrus Wiki/FAQ: http://cyruswiki.andrew.cmu.edu List Archives/Info: http://asg.web.cmu.edu/cyrus/mailing-list.html