Hi James. Can you do a $ telnet [destination] 25 from the other lan to the machine? If you can, then at least it shouldn't be a network firewall issue. If not, can you ping the mail machine from the other lan? If not, perhaps you have a routing problem. Also, you may have smtp configured such that it only pays attention to lan connection requests, although that is less likely. -Steve On 08/19/2012 05:11 PM, James wrote: > Both computers run Linux. > > A port scan of the machine with the open port 25 from inside the same lan. > > PORT STATE SERVICE > 25/tcp open smtp > > port scan from the web > port 25 is open > > port 25 can receive mail. > > A port scan of the machine with the open port 25 from my lan. > PORT STATE SERVICE > 25/tcp filtered smtp > I can't telnet to port 25 of the computer on the other lan so it is hard to debug it. > I tried making this computer a DMZ. > > _______________________________________________ > Linux mailing list > Linux [ at ] lists [ dot ] oclug [ dot ] on [ dot ] ca > http://oclug.on.ca/mailman/listinfo/linux