On 2006-07-31, Nicholas Anderson <nicholas@xxxxxxxxxx> wrote: > I'm new to clustering and was wondering what would be the best solution > when clustering an email server. > > Today we've 1 server with a storage where all mailboxes (mbox format) For clustering, I think it would be better to use Maildir-format for the mailboxes. Then you'll avoid any locking problems on the mailboxes. New messages can be delivered on one machine while other messages in the same mail-folder is being deleted on another machine. If your users are only accessing their email by pop/imap, moving to Maildir shouldn't be any issue. > and home dirs are stored. > I'm planning to use 3 or 4 nodes running imap, pop and smtp, all of them > sharing users' data. > > Should I use NFS or GFS? NFS is very single-point-of-failure.. so definately a clusterfs/GFS. If you can move to Maildir, you should be able to run any number of servers where each server is running all services (imap, pop and smtp), and incoming traffic is routed to a random server trough f.ex. round robin dns. To handle single-node downtime/crash, you'll just need to move the ip-address to an available node. Easily achivable trough f.ex. heartbeat from linux-ha.org, and probably also RH Cluster Suite.. -jf -- Linux-cluster@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cluster
