Spanning Tree Loopguard
Something has always bothered me about Loopguard. First, I've never implemented it in production, so I'm quite ignorant to how it actually works.. Is there a seperate BPDU that is sent between switches running loopguard to act as a keepalive. If a blocked port stops receiving BPDU's, you want the port to transition to forwarding state to provide a redundant path. I guess what I'm trying to ask is, how does Loopguard distinguish between a "real" failure in the network and one that is merely a unidirectional problem between two switches?
Thanks for any help with this very basic concept... I just can't seem to retain a clear picture on this. I'm sure I've learned this before and have just forgotten..