On 7/16/23 5:57 PM, Benny Pedersen wrote:
why accept local envelope SENDER domains on port 25 ?
Do you subscribe to any mailing lists that don't rewrite the sender? Thus your mail server would receive messages that you sent to the mailing list as your SENDING domain on port 25 inbound from the world.
That's just the first example of why this -- let's go with -- workaround -- I'm being polite -- will work most, but not all of the time.
This starts to become a problem when you have multiple servers working cooperatively and communicating over port 25. -- I remember tell of having email cascade through multiple Exchange servers for various questionable reasons.
its safe to reject them
I would not bet on it. Grant. . . .
