N+1 HA setup mobility domain

[Michiel Vercoutter]

Hi,

Do controllers in an N+1 HA setup (different geographic location) need to be in the same mobility domain for AP failover to work?

It seems like some documentation mentions this and some does not. Can anyone confirm if it is necessary?

Thanks in advance!

[balaji.bandi]

Not sure what is the Models you referring here, But high level  technically it supports :

The N+1 HA architecture provides redundancy for controllers across geographically separate data centers with low cost of deployment.

https://www.cisco.com/c/en/us/td/docs/wireless/technology/hi_avail/N1_High_Availability_Deployment_Guide/N1_HA_Overview.html

[Michiel Vercoutter]

My apologies, models are vWLC version 8.10.151.0

In the document you provided, there is no mention of mobility groups.

However, in the following document there is: https://www.cisco.com/c/en/us/td/docs/wireless/controller/8-8/config-guide/b_cg88/high_availability.html#vwlc-and-nplus1-ha

"The Cisco vWLC HA has the following prerequisites:

• The primary, secondary, and tertiary vWLCs should be part of the same mobility group.

• The vWLC in the mobility group should have a uniform set of hash keys to seamlessly move an AP from one vWLC to another. For example, if we have vWLCs, N, in a mobility group, or vWLC, M, and normal WLCs (where M is greater than N), then all vWLCs should have the hashes of other vWLCs in the same group.

• For effective connectivity of the APs on all the vWLCs in a mobility group (including vWLC mobility members in N+1 format), the mobility hash table should contain all the vWLC hash keys."

[Rich R · Accepted solution]

If you want it to work seamlessly then yes you need mobility between them.  Why wouldn't you do that?