WLC N+1

[OliverRehm]

Hi all

I have a question about the WLC N+1 redundancy.

I have 3 Cisco WLC 5520. Can i configure one as Active, one as Standby and the last one will take over when the active and the passiv are down. 

The failover should be like this.

1. Active fails

2. failover to standy wlc

3. standby wlc fails

4. failover to the last wlc.

Till now i just saw examples with several active wlc and one backup wlc. 

Can somebody help me?

Regards

Oliver

[Scott Fella]

Yes that is possible. You can have two pairs in SSO and the third one as your +1. You just define the high availability in the ap to set the primary and secondary.

[OliverRehm]

So i have to configure on every AP the high availability? 

As primary i configure the active wlc, as secondary the standby and where does i have to configure the the thrid (backup)? is this the tertiary?

Or does i have to configure like this:

The active and the standby wlc have the same config and ip`s. So is the Primary Controller are the pair and the secondary are the +1(secondary controller)? 

regards

Oliver

[Rich R]

You can either run 3 separate WLC and the AP is configured with primary, secondary and tertiary WLC
OR as you implied and Scott suggested you can run the 1st 2 WLC as an HA SSO pair in which case they behave like a single WLC from the AP point of view so then the AP is configured with primary (HA-SSO pair of WLC) and secondary (your 3rd WLC).
More discussion: https://community.cisco.com/t5/wireless-and-mobility/n-1-or-1-1-with-client-sso/td-p/3339846
https://www.cisco.com/c/en/us/td/docs/wireless/controller/technotes/8-7/High_Availability_DG.html
https://www.cisco.com/c/en/us/td/docs/wireless/technology/hi_avail/N1_High_Availability_Deployment_Guide/N1_HA_Overview.html

[Scott Fella]

It’s best to configure in each ap. You can script that. To make it clear, you want to have SSO for two of you controllers which will be your primary as they share the same hostname/ip, then the third controller would be your secondary.

So first tell us if you will be doing SSO for two controllers or not. The other option is having three separate controllers in which you have primary, secondary and tertiary.

[OliverRehm]

Hi all

Sorry for the late response.

I need Primary, Secondary, tertiary

Thank you very much

[Scott Fella]

Configure this on each ap, that is how you should be doing this.  You can just build a script and cut and paste if you like.

[OliverRehm]

Hi Scott

Sorry I was a littlebit confused. I have a SSO Cluster and have to configure one as secondary. You still prefer a skript to apply this settings on all AP?

Cheers

Oliver

[Scott Fella]

Yes that is right. Cut and paste is the fastest. Typically all your AP’s would be joined to one controller, even if that is not the case, you can paste the cli commands for all AP’s even if the ap is not joined to the controller as those will just fail and continue.