Two switches connected. Can I route over these?

[btkach]

I have two switches, that are connected via a port channel, two 1Gb ports, in trunk mode.

I have them set to only allow VLAN 66 traffic over the port channel.  This is set in the port channel.

on each side, I have a switch attached, and then a firewall/router.

Question, can I route between the networks attached to each router over the switched trunk?

I think it seems reasonable, but I want some clarification.

I know that firewall/router A is able to see firewall/router B, over the switched.  They are both configured in the VLAN 66 as point to point devices, ie 255.255.255.252 subnet, 2 IP's

Thanks,

[Joseph W. Doherty]

From what you've described, yes you should be able to route across the VLAN. (BTW, from what you've described, you could have also configured the port-channel to be an access port for VLAN 66.)

Unclear what you need clarification about.

[btkach]

Thanks!

What I meant was, clarification as to whether I can send routing information across a switched network, as opposed to sending routing information between two routers that are directly connected.  The directly connected routers seems to be the diagrams I see all the time.  I don't see diagrams with switches connected to each other, with routers behind the switches communicating their networks.  I just wanted to make sure I wasn't sending unwanted information over the trunk that might cause an issue.

[Joseph W. Doherty · Accepted solution]

Ah, understood.

Yes, you can do that.

Switches can extend a L2 broadcast domain so that hosts can intercommunicate.  Hosts include routers.

[Martin L · Accepted solution]

here is example of diagrams with switches needed for complex L3 routing for both IPv4 and IPv6. This is often called L2 topology (physical) vs L3 topology.  Example of L2 topology here is called "Ethernet Switched Cabling Topology".  Compare this L2 to L3 topology. Notice that on left side, Router2, R3, R7, R8 and Sw3 are connected together over shared vlan 10.  Based on L2 topology, you could deduct that the traffic flow from R2 to R7 or 8 is likely via Sw 1 and Sw 3. (Although it could be using other switches as well). Those devices are not directly connected. Sw3 port in vlan 10 represents PC device as well.  This is from old Cisco 360 CCIE workbook that comes with hundreds of configuration tasks for practice.

Regards, ML
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[MHM Cisco World]

R1-SW1-trunk-SW2-R2

You can do that 

You need only subinterface config in each Router.

Or you can config specific vlan to interconnect the two SW.

[Joseph W. Doherty]

BTW, when @MHM Cisco World writes "You need only subinterface config in each Router." that's only true if you also "trunk" between switch and router to host multiple L3 interfaces.  I.e., depending on your goals, switch<>router connection might just use switch access ports while switch<>switch connection is a trunk.

[btkach]

Thanks for the feedback, I appreciate the guidance.