Dave,

> I know this should be easy, but I cannot seem to get the syntax correct
> for ipchains (2.2 kernel) to drop all traffic from a single IP address.  

try this:

ipchains -I input -s 172.16.3.8/255.255.255.255 -d 0/0 -j REJECT 

You could specify the destination address exactly if you wanted to.  This
will reject all IP traffic from 172.16.3.8 .

Don't forget that ipchains/iptables does matching, and stops at the first
match.  If you want a REJECT or DROP to take effect, you need to make sure
that the REJECT/DROP is in the list before an ACCEPT that might also match
that traffic.  This is why I put the -I (insert) instead of -A (append) in
the command above.

HTH. HAND.

--
Jim Ockers (ockers@ockers.net)
Contact info: please see http://www.ockers.net/

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