changing the subnet of WLC 5500 Scope and Its Mgmt IP

[Bilal Hakimi]

Hello Everyone,
I have a challenge related to the WLC 5500 and associated APs (1600, 2600, and 2800). I need to change the WLAN subnet from 172.22.0.0/16 to 10.6.15.0/24. The old WLC management IP is 172.22.243.223, and the new one will be 10.6.15.10. The previous DHCP scope for APs ranged from 172.22.105.10 to 172.22.106.199; the new scope will be 10.6.15.100 to 10.6.15.199. The DNS server in the scope will be 172.22.22.22, and the DNS domain is XXXX.local. I'm feeling quite confused as these devices are quite old, and the task outcome is unclear to me, given that I'm attempting this for the first time. I'd appreciate your valuable insights.

Thank you in advance.
Bilal Ahmad Hakimi

Wireless LAN Controller  Wireless Network Management

[balaji.bandi]

just reading all your replies - so you have just changed IP and you are using same switch port right ?

i lost on this thread-  Hope the switch holding layer 3 gateway 10.6.15.1

FAs 1/0/20 that where the WLC connected ? can you change to different port and test it ?

Switch: on fa 1/0/1 my Laptop connected and on fa 1/0/2 WLC connected, with laptop there is no issue  

as per this test 1 and 2 ports are working. - can you move the config to this port and test it ?

from WLC can you post :

>show interface summary

some reference :

https://www.cisco.com/c/en/us/support/docs/wireless-mobility/wireless-vlan/68100-wlan-controllers-vlans.html

[Bilal Hakimi]

I tried it on many ports, and changed configurations accordingly. WLC is now turned off. But the output of >show interface detailed management is already shared and I shared also logs they both generated.
My laptop has also as gateway the VLAN 115 ip of Switch=10.6.15.1. My laptop and switch can communicate on any port of the switch. But WLC and Switch are having ARP request and respond problem. I dont know why?

[balaji.bandi]

so you have just changed IP and you are using same switch port right ?  

request was not management - 

>show interface summary

This is odd, we have never encounter these kind of issue changing IP lost totally communication - until we see any conflict of IP (guess)  or small bit of information we are missing here.

Do you see any Logs when the WLC plugged in to switch ? (port going up and down)

if you have tried all no success then  as @Rich R mentioned contact TAC.

[Bilal Hakimi]

Here is the Show interface summary outcome
The problem is the device is outdated and has no Service Support, thats why TAC is also not helping.
I already shared logs of my Switch and of my WLC.
I dont have any problem of ports going up and down

[balaji.bandi]

if i were you i will take downtime freshly build and check - since you dont have contract, its hard to tell what is wrong at this time.

you have tried different options and i dont see any obvious reason why this was not working.