Justin, GLBP will face the same sub-optimal routing issues as VRRP and HSRP. Recall that GLBP load balances by assigning different virtual MAC addresses to each AVF (active virtual forwarder) and then having the AVG (actual virtual gateway) respond to ARP requests with alternating virtual MAC addresses of the AVFs. If the GLBP traffic is not isolated, AVFs can be located over OTV, and when the AVG responds to an ARP request with their virtual MAC, traffic will be sent over OTV to be routed, which is a sub-optimal design. Also note that the above MAC filters and route-maps are for HSRP versions 1 and 2. GLBP MAC ACLs will need to filter out the following MAC range: 0007.b400.xxxx You will also need to change the route-map filter to filter out GLBP hellos which use 224.0.0.102 UDP 3222 (HSRP uses UDP port 1985). Austin
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