Wireless Mesh issues caused by spanning-tree loopguard

[Brett Verney]

Hi all,

I have installed 3 APs in a wireless Mesh network (2 x Root APs and 1 x Mesh AP) at a client site. It seems that whenever my Mesh AP fails over to another parent Root AP, spanning-Tree's loopguard kicks in on the switches trunk connected to the Mesh AP for the native VLAN and CCTV VLAN (cameras are connected to the switch) . This causes a 3 minute network outage for the cameras connected every time.

Can loopgaurd even work on a Wireless Mesh setup? The Mesh Backhaul is essentially a bridge between the mesh connected switches, so I'm assuming when the switches receive BPDUs from different switches on the same trunk link, it will cause issues? I thought the Cisco Mesh had it's own inbuilt loop prevention mechanisms.

Client is running RPVST.

Any assistance would be greately appreciated!

Brett

[Brett Verney]

It turns out Loopguard should only be configured on Point-to-Point links. That is; when a single  device is connected to the other end of a given port. Mesh being a shared medium should not have loopguard configured on any of its uplinks.

When a mesh connected switch stops receiving BPDUs (MAP fails over to another RAP for example) the switch-to-AP link is still 'UP' and thinks there is a unidirectional link failure.

10 points for me :)