Switching

Hi

I'm reading up to getting the JNCIS-ENT certification. There is one thing, that I don't quite understand about VirtualChassis. If I have three switches, which are interconnected in a ring matter. Wouldn't this create a loop?

How does the VirtualChassis avoid learning the same MAC-address on different VCP's? As I understand it doesn't use Spanning Tree?

I may have misunderstood the concept. Unfurtunately I have no practical experience with VC.

The topology discovery gives a breif explanation, here is the direct quote:

"All switches participating in the Virtual Chassis system use the Virtual Chassis Control Protocol
(VCCP) to discover the system’s topology and ensure the topology is free of loops. Each member
exchanges link-state advertisement (LSA) based discovery messages between all interconnected
PFEs within a Virtual Chassis system. Based on these LSA-based discovery messages, each PFE
builds a member switch topology in addition to a PFE topology map. These topology maps are used
when determining the best paths between individual PFEs.
Once the PFE topology map is built, the individual switches run a shortest-path algorithm for each
PFE. This algorithm is based on hop count and bandwidth. The result is a map table for each PFE
that outlines the shortest path to all other PFEs within the Virtual Chassis system. In the event of a
failure, a new SPF calculation is performed.
To prevent broadcast and multicast loops, each switchcreates a unique source ID egress filter table
on each PFE"

Cool. Thanks. Just found it in the course material as well. But thanks for posting!