Layer 3 router on a stick?

[alliasneo1]

Hey guys, New to

CCNP

Switch!

I'm just looking into a layer 3 switch config and I have some questions. If I configure a layer 3 switch with say 3 or 4 vlans then then switch will be able to route between the vlans itself right?

So if I have this set up:

Would I still need to configure sub-interfaces on the router so that the PC's can get out of their VLAN and across the network? Or would you generally not connect a L3 switch to another router like this?

The reason I'm asking is because I thought that router on a stick was when you don't have a L3 switch in the network but when you do I can't figure out how you would get the PC's to the router?

Thanks

[Reza Sharifi · Accepted solution]

Hi,

If the switch capable of doing layer-3 and not just layer-2, than you can configure all SVIs on the switch and have the switch route between the vlans for you.  In this case since all the vlans are terminated at the switch, you need to configure /30 between the switch and the router.  You than can run routing protocol on the switch and the router or just use static routes on them. So, in this scenario, you don't need a router on a stick.

HTH

[alliasneo1]

ahh of course, I can just run a routing protocol on the L3 switch to get the packets out across the rest of the network. I see yes this makes sense now thank you