topic Re: WLC 9800-40 HA which DHCP option for APs IP Scope ? in Wireless

WLC 9800-40 HA which DHCP option for APs IP Scope ?

DariuszD — Tue, 20 Aug 2024 15:17:31 GMT

Hi everyone

I enabled in my infrastructure WLC 9800-40 in HA mode (sso). Now i preparing configuration for AP, i will use only one model AP (Catalyst 9136I) so i added new IP scope (for AP) in infoblox with option 43 where i added hex value witch IP primary WLC controller. Im worry about that what's happen when that Primary WLC "will down". IS AP can join to secondary WLC ? i should add another option 43 to IP scope for AP with ip that Secondary WLC ? What is procedure ? Is i can added next option ? ex. option 60 for specific AP model ?

Re: WLC 9800-40 HA which DHCP option for APs IP Scope ?

MHM Cisco World — Tue, 20 Aug 2024 15:20:44 GMT

When primary down the secondary use primary IP so dont worry

Add primary IP only in dhcp op

MHM

Re: WLC 9800-40 HA which DHCP option for APs IP Scope ?

Mark Elsen — Tue, 20 Aug 2024 15:24:53 GMT

- If you are using HA-SSO mode then everything is transparent on failover ; no extra actions needed!

Appendix : (always advised)
- Have an overall checkup of the 9800 controller's configuration with the CLI command
show tech wireless and feed the output from that into Wireless Config Analyzer
use the full command as denoted in green , do not use a simple show tech as input for this procedure

Re: WLC 9800-40 HA which DHCP option for APs IP Scope ?

Rich R — Sun, 01 Sep 2024 16:31:03 GMT

The others have given you the answer already but just to clarify HA-SSO behaves like a single WLC from the AP point of view. Whichever chassis is active looks exactly the same to the AP and no change of IP when they switchover.