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Apply an ACL to both sub interfaces that block traffic from the other vlan.
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Apply an ACL to both sub interfaces that block traffic from the other vlan.

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I have a Cisco 1721 with a 10bt WIC in it.<br />
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I have trunking configured on the fa0 interface and PAT configured on the e0 interface. &nbsp;I have 2 vlans trunked with dot1q to the fa0 interface<br />
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Vlan1: 192.168.20.0/24<br />
Vlan2: 192.168.100.0/24<br />
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PAT/DHCP are enabled to serve both vlans.<br />
<br />
My question is, how do i prevent Vlan1 from pinging/accessing Vlan2 and vice versa?<br />
<br />
Seeing as how both vlans are in my connected routes in show ip route, the router just assumes it should route to them, but I want them segmented, yet still able to access the internet through e0<br />
<br />
Thanks.
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I have a Cisco 1721 with a 10bt WIC in it.

I have trunking configured on the fa0 interface and PAT configured on the e0 interface.  I have 2 vlans trunked with dot1q to the fa0 interface

Vlan1: 192.168.20.0/24
Vlan2: 192.168.100.0/24

PAT/DHCP are enabled to serve both vlans.

My question is, how do i prevent Vlan1 from pinging/accessing Vlan2 and vice versa?

Seeing as how both vlans are in my connected routes in show ip route, the router just assumes it should route to them, but I want them segmented, yet still able to access the internet through e0

Thanks.

How to stop Cisco 1721 from automatically routing between Vlans

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.