Hello everyone! 
I wanted to share my recent experience migrating from MQTT1 to MQTT2 in openHAB. It was a bit of a journey, but I learned a lot along the way, and I hope my experience can help others who are going through the same process.
First, I must admit that I was a bit nervous about the migration. MQTT is such a critical part of my setup, and I didn’t want anything to go wrong. But after some research and careful planning, I decided to give it a shot.
I started by setting up a fresh installation of openHAB on a separate Raspberry Pi. This allowed me to test the MQTT2 setup without risking my main system. I configured mosquitto as my MQTT broker and got a few smart switches working to ensure everything was running smoothly.
The real challenge came when I tried to migrate my main server. I installed the MQTT2 binding and added the Generic MQTT Broker Thing, but I kept running into connection issues. The logs were my best friends during this troubleshooting phase. I discovered that the SSL configuration from my old setup was causing conflicts, so I had to completely redo that part.
After several restarts and configuration tweaks, I finally got the connection to work! It was such a relief to see the broker status turn green. I then slowly started migrating my items and rules, testing each one as I went. I learned the importance of patience and thorough testing during this process.
One tip I’d like to share is to keep your logging levels set to TRACE during the migration. It might generate a lot of data, but it’s invaluable for pinpointing issues. Also, don’t hesitate to reach out to the community if you get stuck. The forums and Discord channels are full of helpful people who are more than willing to assist.
Now that everything is up and running, I’m excited to explore the new features MQTT2 offers. It’s been a great learning experience, and I feel more confident about my setup now.
If anyone has questions or needs advice during their migration, feel free to ask! I’d be happy to help. 