How to join 9102 to existing 1832 cluster

[Engineer101]

Dear Experts, 

I really appreciate kind of beginner level guide (step by step if possible) to understand how to join 9102 to 1832 cluster. 

1) I came to know that 9102 cannot join 1832 but 1832 can so we need to make 9102 master and then join all the 1832s

2) What about the existing configuration of the cluster? is there any way to back it up and restore on 9102 or does it requires a manual configuration on 9102?

[Scott Fella]

Search around for "Cisco 9100 Mobility Express" and you should find some good info.  The matrix also explains what is compatible with what.  Also when you are going from Mobility Express to EWC, you would have to convert the config and not all the config might work.  Look at the matrix to determine what image you need to have and make sure you can obtain that image.

Cisco Wireless Solutions Software Compatibility Matrix - Cisco

[Rich R]

I think you might mean 9105 or 9120 - there is no 9102 AP.

You can use the config converter https://cway.cisco.com/tools/WirelessConfigConverter/ but as Scott said - do not expect all the config to convert - some is not supported at all on 9800 series WLCs, some commands are not supported by the converter and encrypted objects must be manually entered.
It's best to consult the numerous 9800 series config guides and build a new config - refer to the converted config as a starting guide only.

Note that on 9100 series APs it's not called ME anymore - it's EWC (Embedded Wireless Controller) for AP.
https://www.cisco.com/c/en/us/products/collateral/wireless/catalyst-9800-series-wireless-controllers/nb-o6-embded-wrls-cont-ds-cte-en.html