[Dovecot] Imap Timeouts

[Dean Blackburn]

Curtis Maloney wrote:
>> 1) total imap/dovecot crash after a period of repeated "too many 
>> files open" errors... Restarting fixes it, but we'll see if 
>> increasing the open files limit is the answer or not... Never run 
>> into this with anything before, so I'm not confident;
>
> Several other people on this list have run into this problem, and I 
> believe raising the limit has solved the issue for them.
>
I don't imagine anyone has OS X Server 10.4.4 instructions for this? I 
tried to raise the limit via luanchctl, but the suggested "launchctl 
limit 512 unlimited" gave me per user/total limits of 512/12288, instead 
of 512/unlimited... Should I be worried? Doing the math, that seems to 
mean I potentially went from being able to support an unlimited number 
of people/processes with 256 per, to a grand total of 24.

Should I chuck launchctl, and just use ulimit manually?
>> 2) individual user accounts will become inaccessible occasionally 
>> when multiple clients are hitting the account at once (checking from 
>> home and work) - deleting all dovecot* files in the maildir fixes 
>> this, but... I thought Dovecot was supposed to catch this kind of 
>> thing and regenerate the files by itself? I think this is also the 
>> "locking problem" in the sense that once this occurs, the directory 
>> will fill up with lockfiles for each message the user unsuccessfully 
>> tries to load from the client side.
>
> This really sounds like a locking issue more than index corruption.  
> Are your INDEX and CONTROL files stored on NFS?  I believe this is 
> still discouraged, with the next version having better/safer locking.
>
We are not (yet) using NFS, but I went ahead and chose all NFS-safe 
options in the config, as we do* intend on moving to NFS as soon as 
possible to allow for a somewhat* load-balanced server environment. 
Should we hold off, and if so, when can we expect a fix? ;)

Thanks,

-deano

> -- 
> Curtis Maloney
> cmaloney at cardgate.net