Access port loop prevention
I have recently been told by a consultant that access layer loops can be prevented without spanning tree on host ports by using Layer 3 routing. This go's against everything that I know about L2/L3 switching (although I would never call myself an expert on the matterâ¦)
I have been under the impression that layer 3 at the access layer removes the need for spanning tree only on the distribution layer uplinks and not on host ports. Is this incorrect?
Here are my potentially misguided thoughtsâ¦
Moving layer 3 to the access layer removes the need for spanning tree in the core and distribution layers as they are protected by standard routing protocols.
Vlans would no longer be able to span switches in other areas as a result of this configuration.
Host access ports would still need to be layer 2 to connect to servers, workstations, phones, etc and thus require spanning tree to protect these ports from loops.
How close am I?
Lets say that wireless is added to the network. Would you not need switch spanning vlans for roaming devices? If so, does wireless support suggest that you cannot move Layer 3 to the access layer, or is it possible to 'bridge' a wireless vlan to other switches across layer 3 uplink ports through the distribution layer?
All comments are greatly appreciatedâ¦