EFW Support

Support => EFW SMTP, HTTP, SIP, FTP Proxy Support => Topic started by: arco on Thursday 26 November 2009, 10:50:32 pm



Title: mail for example.com loops back to myself
Post by: arco on Thursday 26 November 2009, 10:50:32 pm
Hi,

I have exchange 2007 and i'm forwarding all my internal mails  for outside through SMTP connector to Endian Firewall SMTP.
My mail server IP is configured on Endian Firewall which will recieve emails from internet.
when i'm sending a test from hotmail or any email to my mail server,it's returning back with the following error:
mail for example.com loops back to myself

anyone faced this problem and how to overcome it?

thanks.


Title: Re: mail for example.com loops back to myself
Post by: gyp_the_cat on Thursday 03 December 2009, 10:23:23 pm
I've come across this one before and it can be one of two issues and is more to do with strrict RFC compliance than a technical issue persay.

Issue 1
For example if the Endian is doing an MX lookup and it's getting it's own IP address back it will bounce email back to the sender as sending back to yourself.

Check your internal DNS servers are reporting the destination MX record correctly.

Issue 2
The next fix is more common, in your MS Exchange SMTP connector under delivery and then advanced, make sure that the Fully-qualified domain name box has a different value in it than the one your Endian is using.

Ie if Endian tries to send email to your Exchange and it greets it with the same EHLO name then it will assume it's the same box and not send it.

Hope this helps :)