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hi need to block private i.p addresses on class a and class b networks entering through the external interface on my firewall, any suggestions on an iptables command?
cheers
10.0.0.0 to 10.255.255.255
172.16.0.0 to 172.31.255.255
Do 192.168.0.0 to 192.168.255.25 need to access you box? Only allow what needs to be allowed...
Perhaps you should explain your setup in detail, as well as what other boxes/IPs need access to it, and someone can probably give you more useful answers. You seem to be confusing the difference between untrusted connection (ie: those from the Internet) and trusted ones (ie: those from your private LAN). Presumably you have two interfaces on the firewall. Each will need different rules, because they are two vastly different ingress points. Again, more detail on your setup, and your goals, would help here.
BTW, good on you for using ssh. telnet is terribly insecure.
Are you sure that you have your inside and outside IPs straight. Both the 10.x.x.x and 192.168.x.x IP addresses are private and should not be coming in from the outside. These ranges definitely should be blocked.
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