TCP/IP Filtering Problem

  • Thread starter Thread starter George Jewell
  • Start date Start date
G

George Jewell

Hello,

I'm trying to lock down a Win2K server (Svc. Pak 4) for use as a web server
and want to be as thorough as possible. I'd like to use TCP/IP Filtering,
but have run into a snag. I have it set so that the following TCP ports are
permitted: 21, 25, 53, and 80; and also UDP port 53. The problem is that it
seems name resolution is not working. I can ping sites by IP address but not
DNS names. Also, sending mail with the SMTP server does not work, and adds
this entry to the system log: "message delivery to the remote domain
<domain> failed for the following reason: destination server does not
exist."

When I allow all UDP ports, everything works fine. Obviously there are a few
other UDP ports I must allow - does anyone have any suggestions as to which
ports to open? Thanks.
 
Sorry, I should have gave a little commentary with my other post. I think
you are taking the wrong approach. The articles I included in that other
post give you the right direction to move in. There is a whole *lot* more to
security than fooling around with the TCP/IP Protocol. TCP/IP only involve
Layers 3&4 of the OSI model,...and there is a whole lot more to networking
than that. You need to think in a "bigger picture".
 
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