> > > The main problem is to build a shared storage that can > survive server > > > crashes, where mail will be stored. > > > > Use a SAN. > First of all, such SAN must be very reliable itself. Second, it must > support some kind of global locking mechanism, so several nodes can > use lock to protect file from simultaneous writing. Third, Cyrus IMAP > must lock mailboxes, so several instances on different server can work > with one mailbox without conflicts. Whether Cyrus IMAP use locks or > assumes that he is the only one who access mail box, I don't know. Can > it safely access one mailbox from different servers, I don't know too. A good commercial SAN costs a fortune, but it is very reliable. And did you want a *cluster* or a group of servers? A cluster should operate as if it is a single host, and thus avoid the locking issues. Have a look at Red Hat's clustering product for an example. If our cyrus installation was going to be clustered, RH cluster with a SAN backend is what we would do. Regards, Sarah Walters ---- 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
