The machine connecting to your server can come from any port but you must define an access filter that will allow any port to connect to you destination port. for example you would allow from any port and any address to port 25 on the external IP address. You must also define a tunnel from the external address on port 25 to port 25 on the target machine in the service network or protected network. In the Unix world only the root user is allowed to acquire ports lower than 1024. most processes do not run as root and must acquire a port higher than 1024. So you must allow any port access port 25 or 53. Most DNS and Internet mail servers are Unix based especially in the Universities and Colleges as well as many ISP's.
-----Original Message----- From: tharmon [mailto:[EMAIL PROTECTED]] Sent: Thursday, August 17, 2000 12:39 PM To: gb-users Cc: tharmon Subject: Remote filters If I am setting up a remote access filter for a mail server should I require that all traffic destined for port 25 on my server come from port 25 on the other server? Same question on DNS (port 53). Thanks Tom Harmon, Network Manager - mailto:[EMAIL PROTECTED] Eau Claire Area School District - http://www.ecasd.k12.wi.us 500 Main Street - voice: 715-833-5513 fax: 715-833-3481 Eau Claire, WI 54701
