Hi,
Could you say a few words about Dovecot and POP/IMAP to an NFS mounted filesystem? I thought I saw on the dovecot webpage that NFS is "no way" with 0.99 and "maybe" with 1.x. I was looking for the FAQ and couldn't find it.
My setup is like so: My mail server is a Solaris 9 system, running sendmail/procmail, and qpopper POP. Mail is stored in mbox format. The /var/mail filesystem is NFS exported to another Solaris 9 system that runs UW-IMAP. The user community also has login access to this second system, so there are also local email clients like Pine and emacs using the NFS /var/mail.
So, POP and sendmail/procmail accesses /var/mail locally, while UW-IMAP accesses it via NFS. The user community has been warned to do either POP or IMAP, but not both. There are very few problems with this setup.
I would like to use Dovecot for both POP and IMAP on the two machines. I know NFS is frowned upon, but this has worked for me. Comments and suggestions, please?
Jeff Earickson Colby College
On Tuesday 15 Feb 2005 7:22 pm, Jeff A. Earickson wrote:
I would like to use Dovecot for both POP and IMAP on the two machines. I know NFS is frowned upon, but this has worked for me. Comments and suggestions, please?
Why mbox? Have you read the original maildir documentation by DJB?
http://cr.yp.to/proto/maildir.html
Strikes me that you could deliver it over NFS to the box running IMAP using maildir, with reasonable confidence this is how everything was designed to work. Although you need to check how things like .forward would be handled.
My experience of email over NFS like you have is that it does work well enough. No doubt large implementations may have some fun with NFS locking. But these days I see little need for small organisation to use more than one box for email, providing MTA and IMAP, in which case NFS is an unneeded complication.
On Tue, 15 Feb 2005, Jeff A. Earickson wrote:
Could you say a few words about Dovecot and POP/IMAP to an NFS mounted filesystem? ... Mail is stored in mbox format.
I'd say if you are interested in mailbox corruption, then mbox format on NFS is a pretty good direction to head. If you have users who accumulate large mailboxes (who doesn't?), you might see poor performance as well.
-- Charlie
A: Because we read from top to bottom, left to right. Q: Why should i start my reply below the quoted text?
On 15.2.2005, at 21:22, Jeff A. Earickson wrote:
Could you say a few words about Dovecot and POP/IMAP to an NFS mounted filesystem? I thought I saw on the dovecot webpage that NFS is "no way" with 0.99 and "maybe" with 1.x. I was looking for the FAQ and couldn't find it.
If you're storing indexes in NFS, it should kind of work with 1.0-tests as long as you set mmap_disable = yes and if you don't have lockd set lock_method = dotlock.
There are still some bugs with that setup though, especially cache file probably complains about corruption once in a while. It should fix itself always, but I guess it's possible that it might sometimes return invalid replies to client. Or depends on what the bugs are..
Also doing concurrent accesses to same mailbox in multiple sessions might sometimes give "stale NFS handle" errors which Dovecot doesn't yet handle everywhere.
participants (4)
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Charlie Brady
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Jeff A. Earickson
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Simon Waters
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Timo Sirainen