[plug] mta differences

[Michael Hunt]

On Tue, 2004-04-20 at 10:38, Craig Ringer wrote:

> On Tue, 2004-04-20 at 10:23, Bill Kenworthy wrote:

> > If you are accessing the same account as I and my wife do, the faults
> > evolutions - it graps an imap connection and doesnt let go until
> > forced.
> 
> OK, I'm confused now. Cyrus allows many concurrent accesses to the same
> mailbox (it needs to be able to, as it supports shared mailboxes), so OE
> and Evo should be able to be connected _at_ _the_ _same_ _time_.

I don't really have much need to access the same mail account with two
different clients. Sometimes I access my mail from my wife's machine and
vice versa, but usually it is only for a short period of time and I
disconnect afterwards. The only problem I had was that my evo filters
didn't run, but I was doing stuff to them at the time and not sure if
the two clients accessing it was the problem or me.

> > I actually
> > have to do a forced shutdown on my home evo client to allow my work
> > access to be unimpeded (delete an email in one and it doesnt update in
> > the other and so on)
> 
> Evolution does seem to do some sort of delayed commit of things like
> flag changes, so this sounds like something I could see happening with
> Cyrus. I think Evo only writes flags back to the server when the mailbox
> is closed (by selecting a new mailbox).
> 
> It's worth noting that Evolution's IMAP implementation is less than
> stellar, and the Evolution developers don't seem too interested in
> fixing it. Lots of bugzilla entries refer to 'the imap rewrite' but it
> doesn't seem to be something that's going to happen any time soon. 
> 
> I wish they'd just use c-client as the base, and be done with it. They'd
> get authorization/authentication and SASL support for free. I suspect
> they can't because of threading issues and/or dependencies, though.

Have you looked much into evo 1.5 (development version of 2.0). There
might be some work on that front. Currently it is in experimental or you
could use GARNOME and compile a whole GNOME 2.6 desktop. Most of the
changes are about integrating it with the desktop with lots of eye
candy. To make this happen there is lots of work going on under the hood
but from what you are saying this is more akin to changes in the running
gear rather than a major engine overhaul ???

And written earlier in the thread:

> > > FYI, while there are problems with Cyrus and Outlook clients, it's
> > > used by a lot of _very_ large sites (big universities and ISPs, 
> > > tens and hundreds of thousands of accounts), so I presume the issues
> > > aren't impossible to solve. I haven't paid that much attention, as
> > > I don't have to deal with OE or Lookout.
> > 
> > 
> > I use Cyrus @ home with Evolution on my Linux work station (Debian Sid).
> 
> Hmm... what version? I assume it's 2.1.x not 2.2.x?

Ummm. This is a woody version. Try a few releases earlier than that.

ephraim:# telnet localhost 143
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
* OK ephraim Cyrus IMAP4 v1.5.19 server ready

I understand that the age of the version I am using may have bugs that
have been fixed in the newer versions. When sarge comes out I will look
to upgrade my server (and I'm hanging out for sarge so I can do just
this), but as it ain't broke at the moment I'm not attempting to _fix_
it.

> > My wife on the other hand uses Outlook 2000 on a Windows XP box.
> > Consistently she gets an error message saying that the connection to the
> > IMAP server timed out and that she is now offline (in the mail sense).
> 
> This has been discussed a couple of times on the Cyrus list, but I
> haven't seen a conclusive solution. The problem sees very hard to pin
> down, as most people don't see it at all.

It is kind of strange because it doesn't happen all that often just enough that it is annoying.

With a newer version installed its likely that the problem will go away completely. (Fingers crossed).

> Cyrus's IMAP timeout defaults to 30 minutes, and if OE isn't refreshing
> the connection in some way during that time it _will_ get disconnected.
> It should handle this gracefully, and silently reconnect when the user
> next does anything. If it does not, perhaps you can enable IMAP IDLE
> messages in OE (if it supports that), or increase the timeout to
> something stupid. The following in /etc/imapd.conf should do it:
> 
> timeout: 1440
> 
> (24 hours)

Done. I'll let you know how it goes.

> > Question for those that are using Cyrus in a production environment what
> > are you using for your MTA ???
> 
> Sendmail. We use exim at the gateway to accept incoming connections, but
> all mail that appears to be to the right domain and looks basically
> valid gets chucked through to our internal Sendmail server for
> processing and delivery. Sendmail works extremely well with Cyrus, but I
> know people use it with a _lot_ of different MTAs and I haven't heard of
> any particular MTA-specific problems.

The reason I asked is I am thinking of switching MTA's to Postfix. In fact I found this good up to date HOWTO.

http://www.delouw.ch/linux/Postfix-Cyrus-Web-cyradm-HOWTO/html/

> There are a few MTA-specific limitations - for example, only some MTAs
> support authentication passthrough on LMTP - but you probably won't care
> about them.

The box is behind a firewall and not accessible from the outside world so 

> The more important question is what delivery method you're using. Like
> with everything else in Cyrus, you have a couple of options. You can use
> 'deliver' (debian renames it to 'cyrdeliver' IIRC), but this is
> depreciated and not recommended. You're much better off using LMTP in
> the MTA, and delivering via Cyrus's LMTPd. 

This is what I am currently doing in my exim.conf file. From memory this is what the debian doco told me was the _way to do it.

local_delivery:
  driver = pipe
  command = "/usr/sbin/cyrdeliver ${local_part}"
  return_path_add
  return_output
  prefix = ""
  user = cyrus

> Some people prefer `deliver` because they can use procmail, but most use
> LMTP for the performance and reliability, and are happy with Sieve for
> mail filtering anyway.

I used procmail for a while, but evo filters are fine for me @ the moment. With only one client type accessing the account from one machine server side filters aren't really needed. Later on I will probably look @ something like this.

> I'd recommend using LMTP if at all possible.

Something I'll investigate when sarge is out.

> Craig Ringer

Michael Hunt