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Access Points Registering to anchor controller Instead of Primary WLC



Access Points Registering to anchor controller Instead of Primary WLC


Some of the Access Points register with Anchor Controller instead of Primary Controller.

Configuration has been Verified that All APs are getting DHCP information pointing them to the primary controller and All Ap's are all in the same VLAN.

Even then some of the Access Points register with the anchor controller. I’m not sure how this is even possible to be honest…


DHCP option 43, DNS, L2 broadcast etc.  Are simply Discovery Mechanisms for an AP.

When the AP sends the Discovery Request to a WLC, the WLC responds with a Discovery Reply. In the Discovery Reply, is a list of all the WLC in the mobility group, their current AP count, their max AP count, and their excess availability.

Using this information the AP will join the WLC with the Greatest Excess Availability.

So DHCP Option 43 points to WLCA.  In the Mobility group are WLCA(100), WLCB(100), WLCC(50).

WLCA has 53 AP

WLCB has 51 AP

WLCC has 0 AP.

Which WLC will the next AP join.  It will join WLCC, as WLCC has the Greatest Excess Availability.

So, is your anchor controller in the same mobility group as the 'internal'?

So log into your 'anchor' and set the primary WLC to be the 'internal'.  Once all of your AP have moved.  Change the default mobility group on the anchor to something different.  Then change it on the internal as well in the mobility group configuration.

The reason anchoring works to a different mobility group name, is that you are hard coding the anchoring.

Question: Where is that setting exactly "internal"?

Answer:  In the AP configuration. So Wireless > pick your AP > High Availability

More Information

If they all had to be in the same mobility group, then AP security would work:

Never wanted an AP to register to "Anchor Controller" we just went into: Security > AAA > AP Policies : to open the AP Policies page, and checked everything to include : Authorize MIC APs against auth-list or AAA. Saved the Configurations: even if APs tried to join they couldn't.


This document was generated from the following discussion: APs registering to anchor controller

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Last update:
‎02-28-2013 02:38 AM
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