Wireless Access

I'm looking at potentially having two clusters of controllers in order to be able to have AOS 8.4 (which has some features I really want) but also to maintain some older devices that we may not be able to replace in time. 

 

So, if I have two clusters, one running 8.4 and the other running 8.2, both under the same MM, will the COA VRRP play nicely on the same vlan or do I have to have a different vlan for each cluster?

 

Is there a mechanism for clusters to play nicely with each other, so if a user roams from cluster1 to cluster2, and we have enforce DHCP enabled, what happens?

 

In an ideal world, this wouldn't matter and we'd be able to groups APs onto cluster geographically... but that's not how our world actually works.

Two clusters with COA cannot be on the same l2 management network, because of the vrrps auto-created for COA can possibly conflict. The user vlans can be shared, but not the management vlan.

Do not count on a smooth transition between clusters. Clients are deauthed when APS switch clusters.

Enforce DHCP info is not shared between clusters, but those devices would obtain new leases, anyways.

Yes, VRRP conflict is something I've run into while playing around. I wasn't sure if the MM coordinated this, but good to know it's best to avoid the risk.

 

Not sure what you mean about APs switching cluster. That wouldn't happen, but in a mixed environment of APs a client could conceivably roam between clusters.

 

The issue with enforce DHCP is that a client doesn't necessarily get a new DHCP lease when roaming. So if that roam is across clusters (or across standalone controllers) the client can lose connectivity. 

 

It sounds like, in our environment, it would be necessary to maintain a geographic separation between APs on different clusters. Not always easy but it is what it is.

Design your environment so that there is no roaming between clusters

I think you're missing the point here.... ;)

 

but I have the answers I need.