Should I block inbound port 25 on the PIX 515?
Hi everyone. OK here is our situation. We currently have an Exchange 5.5 server. Port 25 is open inbound and outbound to the Exchange Server. We recently setup an anti-spam server, added a MX record for it, and opened inbound port 25 to it. We then removed the Exchange Server's MX record. Now mail coming to our company from the outside first comes to the anti-spam server and then is routed internally to the Exchange Server. The Exchange Server still sends mail out through port 25. My question is since e-mail is now coming to the anti-spam server first and never directly to the Exchange Server, can I close inbound port 25 to the Exchange? Will this cause any problems sending e-mail out of our company? I would appreciate any advice. Thanks.
read more and respond »Posted 5 years ago by Corbin O'Reilly in Cisco Systems
