Yes, that's why Anycast HSRP was developed. You do not need the HSRP localization with that. There are few trade-offs running FabricPath for DCI. Here are these :
- Dark fiber between DC's. You have a campus enviornment so getting this should not be an issue.
- Default gateway preferably out of one of the DC's, ie. Traffic will always leave and come back from the same DC. You will solve this using the Anycast HSRP.
- Unknown unicast and bcast will be shared across DC's.
-Your MDT traffic (Multicast/Unknown unicast/Broadcast) will also be hair pinned between the DC's. Even if you have source and receivers as the same site, your traffic will go all the way to the MDT root (which might be at the remote site) and come back to the same site. You need to carefully plan the MDT root placement and use the new FP multiple topologies feature to overcome this behaviour upto some extent. The ability to create multiple FabricPath topologies will alleviate this issue to a certain extent, in that groups of ‘local’ VLANs can be constrained to a particular site, while allowing ‘cross-site’ VLANs across the DCI link.
One point to remember that all your Leaf and Spine switches should support this new Anycast HSRP TLV which is exchanged in IS-IS control plane. So you need to upgrade all the boxes to support this TLV bit.
Hope this helps.
-amit singh
