@lukass2000 that should not be an issue as long as the major and minor version number of the software are the same. Yes, a firmware is device specific but in this case it is about the version of the controller software that is running in the device (currently controller version 6.0.x).

When the new controller is delivered, connect it to your network and connect it to your Omada account. 

Next step is to make sure that both the OC200 and new OC220 are updated with the latest stable release. They should both be running version 6.0 of the controller.

Once that is done, follow the instructions here (section "II. Controller Migration") to migrate the entire controller.

I recently performed a migration from OC200 to the SDN version without any issues.

  @lukass2000 

No it will not. It will retain the IP you have set before.

To complete the migration, both the old and new controller have to be in the same network so they can communicate with eachother and the managed devices.

  @lukass2000 yes you can, but make sure you decommission the old one first so you don't create IP conflicts 😉

  @lukass2000 That is up to your personal preference. Port 443 is the default https port so you can just access the on-prem controller directly via https://<host>/

Setting a different port for the https interface is possible (I assume) but doesn't make it better or more secure. Normally you only define a different port if you are running multiple services on a single host/ip and have conflicting ports (e.g. you want to host an Omada SDN solution on a same host that already runs a web server at port 443).

Since you are using a dedicated controller you have no conflicting ports and can just use whatever you like.