Hello experts,
Since 2 months, we have been seeing a strange phenomenon :
We use 2 Edge Transport servers to receive and sent out email messages.
So our 2 MX records resolve to these servers.
A small percentage of our incoming mails is bouncing between our edge transport servers and eventually the TTL is reached and the email is denied sending an NDR to the sender.
so basically :
1. mail received from smtp1 on smtp2
2. mail received from smtp1 on smtp1
3. mail received from smtp1 on smtp2
4. mail received from smtp1 on smtp1
This goes on and on until the timeout...
I have searched in every log and been searching on the web but cannot find a cause or solution.
Can you guys help me ?
Thanks!