Please Advice on Migrating from old WLC to a new one.

[irusev27]

Hello Everyone,
So I have to Migrate from a current WLC that is a cisco 3850 Switch to a new vWLC which I will have to install as a Virtual Machine on ESXI host.
My main concern is migrating the Access Points from the old to the new WLC.  From my understanding, if i pull the plug on the current WLC, the access Points will automatically start looking for a new WLC ( which I would have preconfigured to mimic SSIDs and most other settings from the old WLC). APs should be on the same vlan as the controller so DHCP option 43 probably wont be needed.

If anyone have expiriance or have done that before. I would apreaciate any advice and any caveats I might face.

[Flavio Miranda · Accepted solution]

@irusev27 

 It is indeed simple like that but....You need to check carefuly if your APs supports the image version on the new WLC. AP on the same vlan as the WLC will be able to discory the  WLC by using broadcast and or DNS resolution, if available. 

Would be nice if you could match both WLC version prior the migration. It would be a lot easier as the Access Points would not be required to download new software, which takes time and can cause issue.

If you can not match both WLC version, then, you need to wait for AP to join the new WLC, download the software, install and reload. 

[irusev27]

Flavio Thank for the heads up. You give me lots of hope. I will definately check the WLC versions and see if i can match them. I glad to hear that the process is not that bad.
Flavio for President !

[Flavio Miranda]

LOL...

 Yeah, you can share the WLC version and AP models here and we can help you to double check. I would say that AP/WLC  version would be the bigger concern. 

[irusev27]

AP are 

cisco AIR-CAP3702I-B-K9

cisco AIR-CAP3702E-B-K9

The WLC lives on 2x stacked 3850s :  03.06.06E cat3k_caa-universalk9
When I open the controller GUI : 

Software Version

03.06.06E RELEASE SOFTWARE (fc1)

show version on the switch: (I think the cisco IOS-X is the controller version)

WLC-3850-LV# show version
Cisco IOS Software, IOS-XE Software, Catalyst L3 Switch Software (CAT3K_CAA-UNIVERSALK9-M), Version 03.06.06E RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2016 by Cisco Systems, Inc.
Compiled Sat 17-Dec-16 00:22 by prod_rel_team

Cisco IOS-XE software, Copyright (c) 2005-2015 by cisco Systems, Inc.
All rights reserved. Certain components of Cisco IOS-XE software are
licensed under the GNU General Public License ("GPL") Version 2.0. The
software code licensed under GPL Version 2.0 is free software that comes
with ABSOLUTELY NO WARRANTY. You can redistribute and/or modify such
GPL code under the terms of GPL Version 2.0.
(http://www.gnu.org/licenses/gpl-2.0.html) For more details, see the
documentation or "License Notice" file accompanying the IOS-XE software,
or the applicable URL provided on the flyer accompanying the IOS-XE
software.

ROM: IOS-XE ROMMON
BOOTLDR: CAT3K_CAA Boot Loader (CAT3K_CAA-HBOOT-M) Version 1.18, RELEASE SOFTWARE (P)

WLC-3850-LV uptime is 6 weeks, 5 days, 23 hours, 42 minutes
Uptime for this control processor is 6 weeks, 5 days, 23 hours, 50 minutes
System returned to ROM by Power Failure
System image file is "flash:packages.conf"
Last reload reason: Power Failure

Also is this the correct command to stop the 3850 from being WLC ?

conf t

no wireless mobility controller

[Flavio Miranda]

@irusev27 

 The command is correct

conf t

no wireless mobility controller

You did not tell the model and version of the WLC you are planning to deploy but with AP model AIR-CAP3702 you should be fine with newer WLC model and version 

[irusev27]

Hello Flavio, the new WLC hasn't been installed yet. It's  virtual WLC, that I have to install on a ESXi VM. Apparently it has been bought but the I am still hunting it's license. Once I get a hold of that I'll download vWLC .ova , there are 2 versions one that support less and one that support more APs. I'll probably grab the big one, because the plan is to controll AP from multiple sites over IPSec Site to Site VPN (Palo Firewalls).

But once I implement the new vWLC should I try to match with the same version of this one or am I better getting the latest .(I know this WLC is probably old)

Short story, I am taking over this company infrastructure admin role, and the guy that has been doing it is still here and we are working together, and some stuff are a little wild. This whole transition is new to me.... So far it's been a rocky road

[Leo Laohoo]

If the APs are on 3.6.6 and are 2700/3700 there is going to be strong chance the APs will not be able to download the firmware from the controller due to FN72524 - During Software Upgrade/Downgrade, Cisco IOS APs Might Remain in Downloading State After December 4, 2022 Due to Certificate Expiration.

To cut the AP over to the new controller as well as fix this issue: 

1.  Log into each AP and manually download the AP firmware;

2.  As soon as the firmware upload is completed, configure the new WLC details; 

3.  Reboot the AP.  

[irusev27]

Thanks Leo I will keep that in mind. I will check their Version. And if needed I will manually upgrade them.

[Leo Laohoo]

---

@irusev27 wrote:
And if needed I will manually upgrade them.

---

Trust me, you will have to manually upgrade them because the certificates the AP is currently using has already expired.  

The first sign this bug is triggered is when the AP keeps downloading the firmware and then rejecting the end.  

[Leo Laohoo]

What model of APs?

[irusev27]

I replied to flavio with the info