>ipchains -A input -j REJECT  -s 0.0.0.0 -d $IP.1
>
>(this rejects anything from anywhere (0.0.0.0) to your server's ip
>address ($IP.1)

Just a follow up to Nick's post.  This should be applied to the firewall 
interface that the server is connected to IF you want to block not just 
traffic FROM the internet.  If it's just from the internet, apply it to the 
ppp interface.  If the server is not directly connected to the box that 
runs IPChains then anything that shares the ethernet line through a UTP 
switch or hub (God forbid coax) will still get to the server because it's 
not routed through the firewall.  The "-j REJECT" should be at the end of 
the command.  I would write it as:

ipchains -I input -s 0/0 -d serverIP/32 -i eth[server_or_ 
internet_interface] -j REJECT

Note that I elected to use "I" (insert) instead of "A" (append) which will 
make it the first input rule to be checked.  Otherwise you may have a line 
that allows some form of traffic to the server.

You should be more specific with your topography and then you'll get far 
better answers.  The best so far is the air-gap that Christopher suggested.

Regards,
Michael.


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