John W wrote:
>
> This is a result of an Nmap scan on my box. I am wondering if the open ports
> can be closed or filtered.
Use the following ipchains input and output rules, only modify them to
reflect upon the port or service that you wish to DENY :-D
/sbin/ipchains -A input -i [interface] -s 0.0.0.0/0 [port] -l -j DENY
/sbin/ipchains -A output -i [interface] -d 0.0.0.0/0 [port] -l -j DENY
You can also use the -p option to specify the connection protocol (UDP
or TCP) depending on the service that you wish to block. Use it before
specifying the source or destination of the packet.
It is better practice to set the default filtering policies to DENY or
REJECT all packets and then ALLOW only those services that you need.
Stef
