I've setup a fairly restrictive set of rules for iptables and have been, up to this point, extremely satisfied with its performance. However, I've recently started having some signifiant issues with my cable modem provider and they routinely want to ping and traceroute to my machine. This requires me to take down my firewall and wait for them to finish, then put it back up. I'd like to make, as part of my rule set, ping and traceroute able to get through. So far I've done this for my input chain for ping
-A INPUT -p icmp -j ACCEPT For traceroute I've done this: -A INPUT -p ip -j ACCEPT These appear to work, however, am I overlooking something from a security point of view by allowing any icmp and ip's through? Is there a better way? Thanks, Wm