Physical WLC 9800 Failover

[christophe.ranson]

Hello,

I've 2 Physical WLC 9800 in SSO, and I'd like to know if it's possible to monitor the Management AP Interface to force a Failover  if it's not reachable.

I physically shutted the Interface that carry the AP Management IP to see what's happening, and all my APs were losing connectivity to the WLC.

I find it a little surprising because the interest of Redundancy should be to overcome this kind of issues. If the AP management interface isn't reachable, the Primary Controller should switch to guaranty the continuity of services.

Do you have any ideas?

thank you,

best regards

[Rafael E]

how are the 9800 connected to the wired network?

is this a physical appliance? 

what code are you running on the 9800 WLC?

[Scott Fella]

Well what SSO does it verifies the other controller if up, you shut an interface down, that doesn’t mean that failover should happen. Now have your ap manager use the same interface as the management and that would work for you. Since you shut down the management, then SSO will trigger and you will have a seamless failover. Shutting an interface or removing a vlan from the switch trunk port, will not be detected from the controller. Use the management interface for your ap’s.

[christophe.ranson]

Hello,

I'm using physical appliances, the RP for redundancy and a Chanel Group of 2 TenGig Interface for AP Management and SSIDs.

I understand you're explanation about SSO. But I still find wierd that if AP can't join the WLC, it doesn't try to failover.

As I'm using the RP for Redundancy, the SP for OOB Management and 2 ports fort AP Mangement, I can't mutualise those interfaces. That's why I'm looking for a trigger to force failover when APs can't join WLC anymore.

Thank you,

[Scott Fella · Accepted solution]

Ap failover is when you have more than one controllers in N+1. That failover is dependent on the ap high availability that you configure. This happens when you have N+1 like in the following examples:
WLC 1 + WLC 2
WLC SSO + WLC 2
WLC SSO + WLC SSO

Two separate things you need to understand as this is the same for AireOS controllers.

[christophe.ranson]

Hello,

Thank you Scott for you answer, I'm going for 2 Standalone then.

Best Regards,

Chris

[Scott Fella]

SSO vs N+1 really comes down to comfort. I can tell you that I have ran into issues with SSO which did take down the network, however, you only have to configure one unit versus both.

[Arshad Safrulla]

How do you have the physical WLC's connected? You have to run the heartbeat cable through an upstream switch based on your IOS. If you are running 17.2.1 or higher then you can consider running the Heartbeat cable directly connected