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I have 4 ethernet interfaces on my cisco 2600 router that connect to 4 seperate internal networks.<br />
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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&amp;4 and visa versa.<br />
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I setup an access-list to deny the IP ranges on interface1&amp;3, but ended up blocking all traffic.<br />
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I had:<br />
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access-list 3 deny ip 10.1.2.0 0.0.0.255<br />
access-list 4 deny ip 10.1.3.0 0.0.0.255<br />
<br />
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.<br />
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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.

I had:

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.



How do I block traffic between interfaces on a Cisco 2600 router.

A router is a networking device that forwards data packets between computer networks. Routers perform the "traffic directing" functions on the Internet. The most familiar type of routers are home and small office cable or DSL routers that simply pass data, such as web pages, email, IM, and videos between computers and the Internet. More sophisticated routers, such as enterprise routers, connect large business or ISP networks up to the powerful core routers that forward data at high speed along the optical fiber lines of the Internet backbone. Though routers are typically dedicated hardware devices, use of software-based routers has grown increasingly common.