[Dovecot] Outlook 2000/2003 frequent disconnect issue

[Jeff Ramsey]

On Aug 1, 2007, at 12:10 PM, Timo Sirainen wrote:

> On Wed, 2007-08-01 at 12:05 -0700, Jeff Ramsey wrote:
>> Aug  1 11:58:51 imap dovecot: auth(default): passwd(QUINAULT-
>> ileneyoung,::ffff:10.200.254.110): lookup
>> Aug  1 11:58:51 imap dovecot: auth(default): passwd(QUINAULT-
>> ileneyoung,::ffff:10.200.254.110): unknown user
> ..
>> Perhaps this sheds some light on the matter? Why is it trying to
>> authenticate the user again at 11:58:51 when there was no disconnect
>> after 11:58:47?
>
> Outlook just wanted to create yet another connection.
>
>> And why is it failing? My guess on why it is failing
>> is because the Active Directory Server cannot respond fast enough to
>> handle the second request, after already handling the first, but I am
>> just guessing.
>
> I think the problem has to do with NSS. It probably failed with some
> error, but since unfortunately getpwnam() interface doesn't support
> reporting errors, Dovecot just assumed that the user didn't exist.
>
> I can't think of why this would work any differently with Dovecot
> v0.99.x.
>
> I think you should rather get rid of userdb passwd and configure  
> Dovecot
> to use userdb ldap to connect directly to your AD.
>
> Using / not using nscd might also help.

I did the downgrade back to 0.99.11-8.EL4, which I realize is not  
truly 0.99.x, it's got some 1.0.? updates inserted from Red Hat.

Anyhow, I did not get anymore messages about 'user unknown'  
immediately after the downgrade. However, I was still getting a few  
'IMAP Server disconnected' errors in my Outlook clients. So, on a  
hunch I ran a diff command between the default 0.99.11-8.EL4 conf  
file and my old, known working 0.99.11-8.EL4 conf file, restored from  
a backup, and I noticed that even though I was not using the POP3  
protocol at all, I still have the outlook-pop3-no-nuls and the oe6- 
fetch-no-newmail workarounds enabled, along with the outlook-idle  
workaround. So, I added those two workarounds to the default config,  
and it is working again. No 'IMAP Server disconnected' errors all day  
long.

In 0.99.11-8.EL4, could this outlook-pop3-no-nuls be solving this  
issue, even though I am using IMAP protocol, not POP3?

Since in 1.0.2, the workarounds are on a separate conf line for POP3  
and IMAP, is there an equivalent workaround for Outlook with IMAP?  
The wiki mentions a workaround called 'outlook-no-nuls'. Will that  
one work with 1.0.2 under the IMAP workarounds line? And am I being  
realistic that this may be my issue?

Tomorrow, I am going to start building a test server with 1.0.2 on  
it, to figure out how to make userdb LDAP work with my Active  
Directory. I plan on trying this outlook-no-nuls workaround for  
myself, I was just wondering if there is even a chance that this is  
causing the issue.

Thanks for all of the help, this is a great list.

Jeff Ramsey
MIS Administrator
TMI Forest Products, Inc.
jefframsey at tubafor.com
360.477.0738





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