topic Can you change the RMI-IP on a Cisco Catalyst 9800-40 in Wireless

Can you change the RMI-IP on a Cisco Catalyst 9800-40

Anthony O'Reilly — Thu, 02 Nov 2023 23:22:01 GMT

Hi,

I have two Cisco 9800-40 Physical WLCs on version 17.9.4 called WLC-1 and WLC-2.

I have configured WLC-1 as the master.

When configuring redundancy, I configured one the RMI-IP addresses incorrectly. I saved the config and reloaded. Now I don't have a HA-Pair due to this wrong IP.

I have tried to edit it but it is greyed out. On the command-line, I have also tried unsuccessfully.

redun-management interface vlan 10 chassis 1 address 10.10.10.12 chassis 2 address 10.10.10.13

!!! modification not allowed, finish the unconfig

Chassis 1 address is current 10.10.10.11 which is the WLC-2's IP address. I need this changed to 10.10.10.12.

Hope you can help.

Thanks

Anthony.

Re: Can you change the RMI-IP on a Cisco Catalyst 9800-40

Scott Fella — Thu, 02 Nov 2023 23:48:25 GMT

The only way to change is to go back. That means you would need to break HA and then change what you need to change and then establish SSO again.

Re: Can you change the RMI-IP on a Cisco Catalyst 9800-40

Anthony O'Reilly — Thu, 02 Nov 2023 23:50:11 GMT

Thanks Scot, just did this and now have a HA-Pair.

It's been a long day :-). Thanks for your quick response.

Re: Can you change the RMI-IP on a Cisco Catalyst 9800-40

Scott Fella — Thu, 02 Nov 2023 23:54:56 GMT

No worries... if this is a new setup, you better just practice and get familiar with breaking SSO just in case you have to do that in the future. Best time to document your process also.

Re: Can you change the RMI-IP on a Cisco Catalyst 9800-40

Mark Elsen — Fri, 03 Nov 2023 08:19:50 GMT

>...Thanks Scot, just did this and now have a HA-Pair.
- Good work , you can also verify RMI-IP reachability with (CLI) : test wireless redundancy rping

Re: Can you change the RMI-IP on a Cisco Catalyst 9800-40

aleopoldie — Mon, 31 Mar 2025 14:47:10 GMT

Hello Scott,

What about a cluster of 2 x 9800 WLC configured without RMI but only RP.

If I want to configure RMI, do I also have to break the cluster in order to configure it ?

Thanks,

Re: Can you change the RMI-IP on a Cisco Catalyst 9800-40

Mark Elsen — Mon, 31 Mar 2025 16:14:41 GMT

@aleopoldie ...If I want to configure RMI,do I also have to break the cluster in order to configure it ?
Even more then that ,you have to reboot both controllers simultaneously ,

Ref : https://www.cisco.com/c/en/us/support/docs/wireless/catalyst-9800-series-wireless-controllers/220277-configure-high-availability-sso-on-catal.html
>...
>Step 3. Configure redundancy with RMI + RP pairing type.
>...
>Step 4. Reload controllers.
>...For the HA pair to form and the configuration to be effective, both controllers must be reloaded at the same time once the configuration made at step 3 has been saved.

Re: Can you change the RMI-IP on a Cisco Catalyst 9800-40

Scott Fella — Mon, 31 Mar 2025 18:38:49 GMT

100% @Mark Elsen reload is required just the sma as when you setup SSO.

Re: Can you change the RMI-IP on a Cisco Catalyst 9800-40

aleopoldie — Tue, 01 Apr 2025 07:28:48 GMT

Thank you for your answer @Mark Elsen

Here is the action plan I had on mind :

- Break the cluster (I assume both WLC will have the primary IP address as WMI so I would have to change the WMI's IP address of the secondary WLC to avoid IP conflict,

- Reconfigure SSO with RMI+RP,

- Reload both WLC at once,

Am I right ?

Re: Can you change the RMI-IP on a Cisco Catalyst 9800-40

Mark Elsen — Tue, 01 Apr 2025 08:25:54 GMT

- @aleopoldie Looks good , before rebooting : validate the configuration of the active controller with
the CLI command show tech wireless and feed the output from that into Wireless Config Analyzer

And you may want to do that also , after the standby controller has booted again ,

Re: Can you change the RMI-IP on a Cisco Catalyst 9800-40

Scott Fella — Tue, 01 Apr 2025 15:01:55 GMT

Make sure you have console access, you can always break the SSO cluster and then shut the ports on the switch that the standby is connected to so that you will not run into any duplicate ip address when they both come back. Then you can change the management ip and no shut the ports.

Re: Can you change the RMI-IP on a Cisco Catalyst 9800-40

aleopoldie — Mon, 14 Apr 2025 11:40:10 GMT

Hello Scott,

Following this documentation, I think it is possible to enable RMI without breaking the cluster, isn't it?

I mean, going on the 9800's GUI, under the Redundancy menu > click on RMI + RP, set the 2 RMI IP addresses and apply ?

Re: Can you change the RMI-IP on a Cisco Catalyst 9800-40

leccles — Wed, 23 Apr 2025 20:47:43 GMT

I am running into a similar issue. I have 2 working 9800-80 controllers, we moved to another site/subnet. Before giving them an uplink or connecting them to form an HA pair I tried to use the CLI but it allows no typing in either of the controllers. I rebooted the controller and do see the startup process roll across the window but when I try and type anything after the message "press enter to start" it does nothing. Baud rate was 9600 but found a document to change it to 115200, which I did but it doesn't make a difference, same outcome.

I was finally able to get into the GUI of the primary controller by putting my laptop on the management IP subnet. I made some changes in the GUI CLI and now have access to the mgmt IP address on the network.

During the troubleshooting process I tried to run this command to change the IP of 2nd controller to correct IP/vlan "redun-managment interface vlan96 chassis 1 address x.x.x.x chassis 2 x.x.x.x" but received the error modification not allowed, finish the unconfig

Putting my laptop in the same subnet for controller 2 does not give me access to the GUI.

How can I enable the CLI for both controllers?

I did go ahead and plug in the cable to make them a pair and they paired up, but controller #2 has the wrong IP. Do I need to turn off redundancy --Administration>Device>Redundancy and then reboot to break the HA pair?

Thanks for any guidance!

Re: Can you change the RMI-IP on a Cisco Catalyst 9800-40

Mark Elsen — Thu, 24 Apr 2025 06:36:16 GMT

- @leccles >...Do I need to turn off redundancy --Administration>Device>Redundancy and then reboot to break the HA pair?
I would prefer to go that way, perhaps clearing the configuration on the former standby too. And configure HA SSO again with your parameters. Note that CLI access should always work because it is essential for controller management.
(https://www.cisco.com/c/en/us/support/docs/wireless/catalyst-9800-series-wireless-controllers/220277-configure-high-availability-sso-on-catal.html)

===>Always validate the configuration of the active controller afterwards with
the CLI command show tech wireless and feed the output from that into Wireless Config Analyzer

Re: Can you change the RMI-IP on a Cisco Catalyst 9800-40

leccles — Tue, 29 Apr 2025 17:37:51 GMT

Thank you very much! We checked the console port config and it was wrong, that was why we couldn't console in. Once that was fixed, I tried to turn off redundancy in the GUI of the primary, but it gave me an error. I opened the CLI of the primary and ran "no" in front of the command redun-management interface Vlan97 chassis 1 address x.x.x.x chassis 2 address x.x.x.x and it broke the HA pair. I then changed unplugged all uplinks on the secondary, rebooted both, and changed the configs on secondary. Once they were correct, I reran the redun-management command in the CLI of both and it took. I now have to figure out how to change the primary and secondary. I would like the controller on top in the rack to be primary. The chassis is numbered correctly, I guess the chassis number and primary/secondary are not the same things.

Re: Can you change the RMI-IP on a Cisco Catalyst 9800-40

Mark Elsen — Wed, 30 Apr 2025 05:53:40 GMT

- @leccles In an RP+RMI deployment you need to configure the controller that you intend to be active with chassis number 2
(highest priority)