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I was wondering if a connection comes in on a Cisco router interface. Can that connection be pointed towards a switch interface if said router has a switching module?

I haven't tried it, but I'm assuming you would place that port into a VLAN, which could then be routed to?

  • Did any answer help you? If so, you should accept the answer so that the question doesn't keep popping up forever, looking for an answer. Alternatively, you can provide and accept your own answer. – Ron Maupin Dec 25 '18 at 9:27
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Concretely, yes, that's common where you have a switch inside a router. The following is from a live config on Cisco 867VAE-K9, which isn't modular but is otherwise like you're describing: it has ethernet interfaces which can't take addresses.

interface GigabitEthernet0
 switchport access vlan 87
 no ip address
!
interface Vlan87
 ip address x.y.z.30 255.255.255.252
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Hi and welcome to Network Engineering! We hope you will become a contributing member of our community.

Routers route packets (not "connections") based on destination IP address. If the port is associated with a VLAN that matches the destination address (or next hop), then yes, the packet will be forwarded out the port, provided the destination MAC address is associated to that port.

The router will use ARP to map the IP address to the destination MAC address.

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