Author: Steve Wray Date: To: exim-users Subject: Re: [exim] heartbeat load balancing and exim
Jeroen van Aart wrote: > Wouter Verhelst wrote:
>
>> It is properly supported by exim upstream, and the recommended course of
>> action in case you need a clustered setup. Exim deals correctly with the
>
> There are those, enough of them, who disagree. As I said countless
> discussions can be found, like this one:
> http://mailman1.u.washington.edu/pipermail/imap-uw/2007-September/001574.html >
>> multiple quirks that are part of the NFS protocol, such as certain
>> locking mechanisms not working (exim uses the one that does work on
>> NFS), the fact that the filesystem may not be available when exim tries
>> to write to disk (in which case exim will delay delivery, or return a
>> 4xx response depending on what file it wants to write), and the fact
>> that multiple queue runners may be active at the same time (which is not
>> a problem even if you do it on the same host).
>>
>> Exim does not 'sort of' work with NFS. Exim works great with NFS. Even
>> if you want to write to mboxes over NFS, exim will not corrupt them
>> provided you set your transport up to use lock files rather than flock
>
> I am sorry but you perfectly point out why NFS would be a bad idea. It
> requires exim to work around NFS' flaws instead of just working, like
> when it'd access a real filesystem. How can you say exim works great
> with NFS if you have to set up your transport to use lock files rather
> than flock, or else files may become corrupted. That to me sounds like
> it does NOT work great, but works sort of, if you're careful and avoid
> the problems.
>
> In that same line of thought qmail works great IF you apply the 600 or
> so patches it needs to actually turn it into something resembling an MTA.
