Internet Mail Routing (Rejected)

[gotribe17]

We have a user who is trying to email anyone@climacolaw.com. These emails just sit in my que and never go anywhere. I talked with their IT guy and they have been sending and receiving email as normal. They are not part of any restricted emails domains on my address book.

I'm thinking maybe a DNS issue? The other interesting thing here is their IT guy had me try to telnet to his port 25 and it would not make a connection. The last time we were able to send this law firm an email was 4-30-2004.My mail server is sending and receiving everything else.

Oh yeah and BTW we get a Server not Responding error as response.

Any ideas would be greatly appreciated.

 

[Packet7]

Hello,

We had a similar issue where the client started using RDNS (Reverse DNS). How does your mail server look from the outside? Do you NAT to your FW's public IP?

If so, make sure you have a PTR record for your mail server. Some mail systems lookup the PTR record to verify your who you say you are. This simply points back to your IP and provide a method of verification.


Rgds,

John

 

[woonjas]

the fact that it was not possible to telnet to port 25 on the customer's server points towards another source than domino, perhaps some firewall filter's acting up, either on your end or theirs.

Woonjas
IRC: #notes on EFNet