Hi all:
We're planning to deploy a large e-mail system storing maildirs in a NAS system through NFS. One of the options we're thinking on is using Dovecot+EXIM.
As far as I've read in both project's documentation, both services implement locking allowing multiple servers to access the same maildirs in order to distribute the service load. However, I can't find any information explaining whether both locking mechanisms are compatible, whether any additional configuration is needed both in Dovecot and/or EXIM, or even whether any locking synchronization between both services is needed/recommendable at all.
The only remote clue I've found is that, according to Dovecot docs: "Because Dovecot uses its own non-standard locking (dovecot-uidlist.lock dotlock file), other MUAs accessing the maildir don't support it." (but EXIM is not a MUA, anyway)
Anyhow theoretically MailDir could even be considered free of locking problems, but I'm not sure of the real implications of putting together several Exim and Dovecot installations pointing to the same NFS filesystem.
Any knowledge/experience/link/clue on this would be greatly appreciated.
Thanks in advance,
Daniel Campos