WLC 2504 Fallback after Failover does not work

[Christian Ammann]

Hi

I have two WLC 2504 with 7.6.100.0, one of them defined as HA. I have an RF-Group, AP Fallback is enabled and Failover works perfect. Fallback of the AP's works, when I define Primary and Secondary Controller on the AP's High Availability Tab, but not when I just define 'Back-up Primary Controller' IP and name under All AP's General Configuration. Can somebody help?

Thanks in Advance

Christian

[Sandeep Choudhary]

Hi,

You can now configure the name and the management interface IP addresses of the primary, secondary, and tertiary controllers for each AP from the Wireless > Access Points > All APs > Select AP > High Availability Configuration page on the controller. With the IP address information, each AP can now send discovery messages to the primary, secondary controllers, even if those controllers were not discovered through the other discovery mechanisms.

From the controller Wireless > Access Points > Global Configuration page, you can define a backup primary controller (which acts as the secondary controller) and a backup secondary controller (which acts as the tertiary controller) globally on the controller. These controllers are defined with their name and their management interface IP address. This information is sent to any AP joining the controller, and you do not need to define secondary and tertiary

controllers AP per AP anymore. The configuration is flexible. If an AP already has a secondary controller configuration, it ignores the backup primary controller information received from the controller.

Where you are configiguring the 'Primary-Backup' and 'Secondary-Backup' Controllers, only takes affect if the Primary/Secondary/Tertiary are down.  These are really 4th and 5th selections respectively.

In addition to the option to configure primary, secondary, and tertiary controllers for a specific access point, you can now also configure primary and secondary backup controllers for a specific controller. If the local controller of the access point fails, it chooses an available controller from the backup

controller list in this order:

• primary
• secondary
• tertiary
• primary backup
• secondary backup

http://www.cisco.com/en/US/products/ps6366/products_tech_note09186a00809a3f5d.shtml#backinfo

Regards

[Christian Ammann]

Hi and thank you for your answer. Unfortunately it does not solve my problem. As I wrote, I defined nothing on each AP under Wireless > Access Points > All APs > Select AP > High Availability. (That's because I have about 50 AP's )

On the Primary Controller i defined the HA Controller under Wireless > Access Points > Global Configuration as primary backup and I didi the same on the HA Controller for the Primary Controller as primary backup.

So Failover to the HA Controller works perfect, but I do not get back the AP's to the Primary Controller after it is online again. When I set the HA Controller Offline, then the AP's goes back to the Primary Controller immediately.

I suppose, there are two possibilities:

- Fallback only works when I define primary/secondary at Wireless > Access Points > All APs > Select AP > High Availability

- I defined something wrong at Wireless > Access Points > Global Configuration.

Regards

Christian

[Sandeep Choudhary]

Hi,

As per my last post.

If AP cant discover Primary/sec then only it will go for backup primary and backup secondary Controller:

When using both the local (primary, secondary, tertiary) and global  backup configurations, the locally configured settings take precedence  in the event of a controller failure. If an AP is not able to join any  of the locally configured controllers, it then tries to join the global  backup controllers.

There may be a situation where APs do not move back to the configured  primary controller when that controller is back on the network. When  this happens, ensure that AP fallback is enabled under “Controller ->  General” section.

Regards

[Sandeep Choudhary · Accepted solution]

Option 1 – Specify primary, secondary, or tertiary controllers on each AP.

Option 2 - Specify primary backup and secondary backup controllers in Wireless->Access Points->Global Configuration.

If you configure AP Fast Heartbeat, it will help APs to detect WLC failure more quick independant of any other settings.

If  you have both option 1 & 2 configured, always option 1 will take  precedance (so no point of configuring both), in case all primary,  secondary, tertiary controllers failure it will use globack backup  configured.

More info:Nice written by Rasika

https://supportforums.cisco.com/thread/2260980

Regards

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[Christian Ammann]

I have absolutely no idea why, but suddenly it works

Thank you for your support.

[Sandeep Choudhary]

Glad that finally U got it.

Can you please mark this question as answered, it may help others.

Regards