How do I block traffic between interfaces on a Cisco 2600 router.
Posted on 2005-05-05
I have 4 ethernet interfaces on my cisco 2600 router that connect to 4 seperate internal networks.
What is the best way to block traffic originating from interface 1 from going to interface 3, but still allow it to go to interface2&4 and visa versa.
I setup an access-list to deny the IP ranges on interface1&3, but ended up blocking all traffic.
access-list 3 deny ip 10.1.2.0 0.0.0.255
access-list 4 deny ip 10.1.3.0 0.0.0.255
with access-list 3 applied to inbound on interface 1, and access-list 4 applied to inbound on interface 3. This led to all IP traffic being denied however, which forced me to console in and remove the access-list.