Hi All,
How do I make sure that sendmail outside the server is blocked? How do I make sure the port 25 is blocked on the firewall? How do I determine if port 25 is used or other ports?
Thanks in advance for any commment you may add.
Try to telnet to the IP with the port number. If its "Trying..." for long, it means its blocked. If its a home box, most ISP's intentionally block the mail port (25) to keep users from hosting their own mail servers.
Check out on the senmail entry in the /etc/ipf/ipf.conf file