I use Zigbee2MQTT with a Zigbee stick (I do not remember which one but it is compatible with Z2M and ZHA).
I would like to temporarily power down my Zigbee2MQTT container and try ZHA on the plugged-in stick.
My question: is there anything in ZHA that can modify the stick and break its useability? In other words, is a stick strictly read-only (outside of a manual firmware update) and using Z2M or ZHA is just a matter of configuration of the services and pairing?
If you start ZHA, there is an option when adding the dongle something like “keep existing network.”
If you choose that option, ZHA should start discovering your existing devices. It can take a while for all devices to be seen. They will come in using ZHA’s default naming conventions. I wouldn’t add or remove any devices under ZHA if trying this.
I would only try this with a cc2652 based coordinator. If the stick config gets hosed, z2m supports restoring the TI chips, but does not do so with SI Labs chips.
But…
Coordinators are not that expensive. I’d recommend I getting an extra stick to test ZHA side by side with z2m. No need to risk(however unlikely) the existing net. Of course that depends on the number of devices - rebuilding a 10 device net is not a big deal, a 100 device net is.
For ZHA testing I’d get an SI Labs EZSP based stick (ZBDongle-E, SkyConnect, etc) to allow testing the Thread stuff as well. If you decide not to use ZHA at all, the stick can be flashed with router firmware and used to strengthen your existing net.