Firewall rules for servers, UDP

Lucas Holt luke at
Tue Aug 19 11:32:05 PDT 2003

I want to setup a firewall (ipfw) on my freebsd 4.8 p3 server.  The 
machine runs web, ftp, ssh, dns, smtp, and imap to the outside world.  
Does anyone have any links to example rules for servers?  (I've already 
looked at the handbook and man file)

My problem lies in UDP rules.  I think I have TCP figured out.  My 
first attempt blocked off DNS queries from the machine outward.  I 
could query the DNS server, but apps could not do lookups.  i figure it 
has something to do with ports above 1024, but I'm not sure how to 
define a rule with multi ports in a range, plus I don't know how high 
to go above 1024.  Is this the right action?  Ideas on syntax?

Lucas Holt
Luke at
________________________________________________________  (Jewel Fan Site) (Free blogging)

"Only two things are infinite, the universe and human stupidity, and 
I'm not sure about the former."
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