Cyrus IMAP, sendmail and LDAP

John Arthur lists at
Wed Jul 7 22:07:43 EDT 2004

The way you have it setup now Sendmail accepts all mail before trying to
deliver it via cyrus (just like most secondary and some primary mx servers
do). So if I send 1000 emails to non existant users your sendmail will
accept them all (regardless of weather they exist or not) before trying to
deliver them to cyrus. Because I'm a spammer I've used fake return addresses
so you now have 1000 bounces sitting in your mail queue (which Sendmail
keeps trying to resend every hour)until they expire putting a strain on your

Every time I have setup LDAP routing for a domain (primarily on the mx
servers but also on the cyrus system) it has resulted in a 80% to 90%
reduction in mail traffic and server load.

-----Original Message-----
From: owner-info-cyrus at
[mailto:owner-info-cyrus at]On Behalf Of AJ
Sent: Thursday, 8 July 2004 8:21 AM
To: info-cyrus at
Subject: Re: Cyrus IMAP, sendmail and LDAP

Thanks.  I have reviewed the sendmail page numerous times, but my
question is what is the difference between the way I have things set up
now, i.e just using cyrus as a local mailer, as opposed to ldap_routing.
I am not sure why one would go one way or the other, just trying to clarify.


Andrzej Filip wrote:
> AJ wrote:
>>  My setup is cyrus, sendmail and openldap for all users data.
>> The way I have things set up now is sendmail use cyrus local mailer,
>> and is not compile w/ LDAP support, so if a mailbox does not exist in
>> cyrus,   it gets bounced.  Sendmail does not do user/mailbox lookups
>> via LDAP.
>> This seems to work ok, but on the net I have been reading most people
>> set up sendmail to look at ldap for users, rather than cyrus.
>> Can some people share their setups on how they implement these three
>> together?
> * LDAP ROUTING (sendmail)
> *  Autocreate INBOX patch for Cyrus
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