[c-nsp] L3 vs. L2 trunk connections to a 6509 core. Easyrouter-head question.

[Dean Smith]

Yes If you want "All layer 2" or "all layer 3" but It doesn't have to be so
black & white.

You can have the 3560 acting as Layer 2 for some VLANs - switching the
relevant physical ports to trunks with that vlan allowed,  and Layer 3 for
others - with a local (on the 3560) SVI and using the local routing to
determine the switch exit path

The only caveat 'd ad to your list is that if you have ip routing enabled
your default should be a proper static route "ip route 0.0.0.0 0.0.0.0
172.16.15.255" (or via dynamic eigrp of course). The "ip default-gateway"
command is only used when ip routing is fully disabled.



>Therefore is it accurate to say that if I want the 3560 to be a Layer 2
>device only I have to:
>- disable ip routing and eigrp
>- define a management interface (the current VLAN1 SVI)
>- default-gateway for the management vlan on the 3560
>- trunk as described above
>
>Or if I want the 3560 to be a Layer 3 device I have to:
>- enable IP routing
>- enable EIGRP consistent with the core router
>- choose an completely different VLAN for the access switches and give
>them an SVI at the access switch and let EIGRP handle the routing (??)