wlc redundancy?

Joerg Karschau · ‎11-19-2007

hello,

at the moment i have two 4404-100 controllers. in the backbone we have two 4500 switches. the two 4500's are connected via an 4 gbit channel. for l3 redundancy we

use hsrp. the controllers have the following ip configuration:

controller 1: vlan 234

management -> port 1 -> 172.17.240.1

ap manager 1 -> port 1 -> 172.17.240.2

ap manager 2 -> port 2 -> 172.17.240.3

ap manager 3 -> port 3 -> 172.17.240.4

ap manager 4 -> port 4 -> 172.17.240.5

controller 2: vlan 234

management -> port 1 -> 172.17.240.6

ap manager 1 -> port 1 -> 172.17.240.7

ap manager 2 -> port 2 -> 172.17.240.8

ap manager 3 -> port 3 -> 172.17.240.9

ap manager 4 -> port 4 -> 172.17.240.10

the lwapp ap's are all in different building vlan's and use dhcp option 43. runs perfect. now my question. is it possible to use port 1 and 2 from

controller 1 and 2 on the first 4500 and the other ports an the second 4500? in the backbone we are using rapid spanning tree. anything i must configure

on the controllers?

thanks and best regards,

joerg

ps. software version is 4.2.61.0

Michael Odom · ‎11-19-2007

I'm not sure that will work the way you think it will work. When you configure the lightweight AP's for controller preference, you do so by the SNMP name of the controller. The problem with that is I do not believe the AP's will spread across your interfaces, and what you'd end up with may be unpredictable.

In your situation I'd recommend switching all 4 ports to etherchannel, and putting one 4404-100 on one of your 4500's, and the other 4404-100 on your second 4500. For redundancy, limit your deployment to 100AP's, so if either 4404 or 4500 fails, you have capacity to handle the AP's on the other controller. This is how I've deployed my controllers.

You might be able to use VSS with the controllers in etherchannel to get the results you desire, but I'm pretty sure VSS is only on the 6500's.

Joerg Karschau · ‎11-19-2007

this is what i also think. for testing i have done this configuration. the lwapp ap's spread over all four interfaces. but the configuration isn't running stable. randomly both controller are ending in an reboot loop. nothing to find in the logs on the controller and 4500's. when i shutdown the redundancy ports all is fine again. i think the lag configuration is the best solution.

joerg