MESH AP migration from Physical AireOS to Virtual AireOS

[lsp2310]

Hello All,

I have question / questions on AireOS Mesh network setup.

We have MESH network of multiple old APs - AP3702s, AP1551s, AP1572s.

We would want to move the APs from the old physical AireOS WLC 8500 series to AireOS vWLC. Now you may ask why not on 9800-CL. Long story short - a lot of management back and forth for the stuff we wanted thats never approved. The second reason to move to AireOS WLC is a lot of AP1551s are not supported on the C9800-CLs. We decided to move to vWLC from 8500 series WLC is to reduce the hardware failure dependency as WLC 8500 are EOL and EOS with no hardware replacement from Cisco.

Here is what I am trying to do, I have 2 test APs on the desk. AP 3702s, I have set one up as RAP and second one as MAP, it joins the old physical controller and everything is good and happy. MESH tree shows correct neighbors, RAP is physically connected to access switch and MAP is connected to only external power source, it connects to RAP via wireless link. Now, I changed the MAP's WLC in the high availability. Removed the MAC addresses from old physical WLC and added it in the new vWLC, and as expected the MAP went down looking for RAP. I then changed the WLC for the RAP in the high availability, the RAP upgraded its image from the new vWLC and it joined the new vWLC as RAP (Here I removed the MAC addresses of the RAP from ). Now the MAP is still looking for RAP, I rebooted the MAP and it made no difference.

Software versions:

Old WLC8500 - 8.5.151.0
New vWLC - 8.5.182.0

In the lab MESH setup, I have hardcoded the MAP to prefer the RAP as parent in the Preferred Parent section under MESH settings.

Mobility - We tried building mobililty between 2 of the WLCs, but the MAP in new vWLC is not able to join the RAP in old WLC, in a nutshell it didnt work so we decided not to go through that route.

Now questions:
1. Can I have MAP and RAP on a different software version? In real life we can not physically connected the MAPs to the network. So based on the approach above
2. In the console of the MAP I can see it is trying to establish the neighbor relationship with RAP but it times out. The RAP light turns blue during that attempt but later turns green after it times out. For some reason I feel I am closer to the solution but not close enough.
3. Passphrase - Old WLC didnt have any passphrase configured in the new vWLC we have a passphrase configured. I did remove the passphrase as soon as RAP joined new vWLC. Question - is default passphrase different on different models and versions of WLCs?
4. What other process / migration procedures that I can explore / follow to migrate the APs from old physical WLC to virtual WLC?

Thank you

[Mark Elsen]

  - @lsp2310      >...Now you may ask why not on 9800-CL. Long story short - a lot of management back and forth for the stuff we wanted thats never approved. 
                          That's very bad news, the aireos platforms are being phased out and going end of support
                           It's  not a good idea to start such a project at all

  M.

[balaji.bandi]

For seamless upgrade always use same version of code in virtual environment, and Move test AP or use TEST AP working state and migrate production environment AP to Virtual environment and test it.

as long as the configuration of old and new are same, then your migration will be smooth and easy.

if this is critical setup always test in Lab before you make it in production environment, so you learn lessons, or have TAC engineer standby if enounter any issue.

[Saikat Nandy]

Answers:
1. Can I have MAP and RAP on a different software version? In real life we can not physically connected the MAPs to the network. So based on the approach above. Ans- No you can not have RAP & MAP in different SW. The logical explanation is, even though the MAP is talking o the RAP but at the end it is talking to the WLC. So it has to be in sync with the SW running on WLC.

2. In the console of the MAP I can see it is trying to establish the neighbor relationship with RAP but it times out. The RAP light turns blue during that attempt but later turns green after it times out. For some reason I feel I am closer to the solution but not close enough. Ans- There can be multiple reasons for this. Please verify the config again and you can refer this doc

3. Passphrase - Old WLC didnt have any passphrase configured in the new vWLC we have a passphrase configured. I did remove the passphrase as soon as RAP joined new vWLC. Question - is default passphrase different on different models and versions of WLCs? Ans- Default password remains same.
 
4. What other process / migration procedures that I can explore / follow to migrate the APs from old physical WLC to virtual WLC? Ans- Your process is pretty much okay. Since you had the option, keeping both the controllers in same version and doing the migration would have been easier. At the end of the day if you can stop the MAP to download the image from WLC, you do save a lot of time.

This doc has a bunch of good info. Worth a look.