How to deploy HA between 2 sites with each having 2 WLC working as SSO

[mm-501]

Hi guys

I’m struggling with a situation on my work that needed to be deployed.

The current situation we are in at the moment, we have multiple branches that contains an AP’s connected to single WLC in one sites which is It is considered as SPOF.

In our case We have 2 sites let’s name it A and B.

We intend to deploy a separate wireless network in A and B sites having 2 WLC in each working as an HA making it 4 in total (Primary and secondary in each site), which I believe it is called stateful switch over (SSO).

,in addition we want the WLC in the 2 sites to work as a backup for each other, so for example in case of any complete shutdown or lack of consumed power in site A, the AP’s will directly connects to the WLC in site B with a unnoticeable delay, and we reconnects to the WLC in site A when it powers on again.

We have other multiple small branches but it connects to one of A or B sites depending on the distance.

Any hint will be helpful

[MHM Cisco World]

Two site two wlc sso' I dont think it work' wlc sso need l2 connection

Best is config two wlc and make AP select close wlc 

MHM

[marce1000]

         >...., so for example in case of any complete shutdown or lack of consumed power in site A, the AP’s will directly..
  Ok , but will the APs then remain alive too ? Will it be reasonable to keep  a wireless service running for customers ?
  Anyway you can look at N+1 redundancy between HA-SSO pairs on different sites , for instance.

 M.

[met-m2000]

I'm afraid my idea wasn't clear enough, i will try to explain with a an illustrative image

so, let's imagen that in Site the controller management IP is 192.168.1.50/24 with its having its own standby controller if its fails.

the other site controller management IP is 1.1.1.50/24 with its having its own standby controller if its fails.

I want if site A both primary and secondary controller fails it migrates all its AP's and wlan to the controller in site B until it the primary controller in site A reconnects back, and vise versa.

[Flavio Miranda]

Hello @mm-501 

One possible scenario for you would be the AP from site A to have the WLC cluster management IP address from site B as a secondary WLC in the AP availability tab.  The same you can do on the site B using the management IP address from site A.

This way, if one side goes down, the AP will migrate to the other side and this is called HA  N + 1.

  Keep in mind, however, during the AP migration there will be clients disconnection as the AP will reload.

For WLC 9800 look at "Configuration on Access Points"

https://www.cisco.com/c/dam/en/us/td/docs/wireless/controller/9800/17-4/deployment-guide/c9800-n-plus-1-high-availability-wp.pdf

[met-m2000]

Meaning, is it impossible to have N+1 and SSO at the same time ?? 

[Flavio Miranda]

Actually the idea I provided uses both at the same time. The HA SSO will be used between WLC on the same site, this is what you have today.
 The N + 1 is done by pointing  the high availability tab on the AP to the other site on the Secondary WLC option