Two WLCs by option 43?

[helder-ganhao]

Hello,

I need to configure a switch to use two different models of APs wifi who connect to two different WLCs (because compatibility).

I already have one model of AP who use the option 43 in switch DHCP pool to go the WLC.

Now I need to use another model of AP in the same switch, o need another WLC.

Can I configure the DHCP pool with another "option 43" line? One primary, the other secundary? How?

How can I do this (detailing) correctelly?

Thanks.

[Flavio Miranda · Accepted solution]

@helder-ganhao 

 Use a different DHCP scope and add a option 43 on the new scope. There is not way to use two option 43 on the same DHCP scope.
 

[MHM Cisco World]

https://www.cisco.com/c/en/us/support/docs/wireless-mobility/wireless-lan-wlan/97066-dhcp-option-43-00.html

Op60 is solution' where dhcp server use op60 to detect AP types and then provide op43 depend on that.

MHM

[eglinsky2012]

I use both option 43 and DNS (cisco-capwap-controller.your.domain) so any AP booting up is aware of both controllers. AP’s that are supported by both are liable to go to either controller, but you can change the AP’s HA settings to force them to the desired controller. 

[M02@rt37]

Hello @helder-ganhao 

Two things to consider, option 43 is prioritized over DNS during the discovery process. Configure Option 43 to point to the most relevant WLC for APs in each subnet. DNS redundancy is helpful for failover and for APs that may bypass DHCP-based discovery.

[Rich R]

One more option to add to the mix of options the others have suggested already...
You can specify more than one WLC in option 43.  See the example in the link @MHM Cisco World provided.

F104 means 4 bytes of IP address (= 1 WLC)
F108 means 8 bytes of IP address (= 2 WLCs)
We use this as standard to specify WLCs in 2 different data centres for resilience. 
Once the AP has landed we use AP HA to specify primary/secondary WLC.

[Haydn Andrews]

Few things
if the two WLCs are due to APs not being able to join one due to code version/ support
You could do a Option 43 with 2 WLCs, with the higher code version first
As others have said it will mean that there potential APs will join wrong WLC if they support both WLCs

Option 60 an option
Seperate AP management VLAN would be the cleanest solution.