Hi,
I've a 5.5 installation hosting 3 domains. Originally we had one - with an MX record pointing to our mail relay which in turn forwarded it onto the exchange box. Relaying problems were covered by the usual accepted method of setting routing restrictions and the domain itself was set up within the routing tab for the internet connector to accept that domain as inbound only. All worked fine with mail for unknown recipients generating the usual errors.
Recently we added a second domain - similar setup to the above. It has an external MX record feeding our mail relay - again forwarding on to the exchange box. All worked fine.....
Now we've added a third in an identical manner. Mail to a proper reciepient will be accepted and delivered. However, a mail to an unkown recipient will generate a mail loop error (names changed to protect the innocent) which is forwarded to the sender and postmaster from the exchange server:
<info@abcdefg.com> info@abcdefg.com
MSEXCH:IMS:abcdefg:abcdefg:abcdefg_EMAIL1 0x80040C02 (00050311) Maximum receipt headers exceeded (possible mail loop).
It looks like mail to an unknown mailbox is sent OUT again by the exchange server. It arrives at our mail relay which determines it is destined for our exchange server and send it back in again.
I've gone over the configs for our domains and they all look similar. I've confirmed that it happens for verious unknown mailboxes and not just one stray forwarding rule.
Any thoughts on ways to track this down?
I've a 5.5 installation hosting 3 domains. Originally we had one - with an MX record pointing to our mail relay which in turn forwarded it onto the exchange box. Relaying problems were covered by the usual accepted method of setting routing restrictions and the domain itself was set up within the routing tab for the internet connector to accept that domain as inbound only. All worked fine with mail for unknown recipients generating the usual errors.
Recently we added a second domain - similar setup to the above. It has an external MX record feeding our mail relay - again forwarding on to the exchange box. All worked fine.....
Now we've added a third in an identical manner. Mail to a proper reciepient will be accepted and delivered. However, a mail to an unkown recipient will generate a mail loop error (names changed to protect the innocent) which is forwarded to the sender and postmaster from the exchange server:
<info@abcdefg.com> info@abcdefg.com
MSEXCH:IMS:abcdefg:abcdefg:abcdefg_EMAIL1 0x80040C02 (00050311) Maximum receipt headers exceeded (possible mail loop).
It looks like mail to an unknown mailbox is sent OUT again by the exchange server. It arrives at our mail relay which determines it is destined for our exchange server and send it back in again.
I've gone over the configs for our domains and they all look similar. I've confirmed that it happens for verious unknown mailboxes and not just one stray forwarding rule.
Any thoughts on ways to track this down?
