I think first you need to know which channel is receiving this payload - only those which are of type NumberValue are of interest.
Once you know it you may have an idea who/what is sending the payload.
Are transformations like JSONPATH in use which may extract such string instead of a number ?
Found it. I noticed it was every 5 minutes so I looked in my crontab and I have a script to get the hard drive temperature of /dev/sda and send via Mqtt but as I am testing the migration on a virtual machine that doesn’t exist as a physical disk and will fail.
I think I have finally managed to get the migration to work.
One issue was I didn’t upgrade to the latest 3.4 version. I went to it by running:
apt install openhab=3.4.5-1 openhab-addons=3.4.5-1
The zulu17 version I was using was one of the issues.
I am now using:
openjdk 17.0.8 2023-07-18 LTS
OpenJDK Runtime Environment Zulu17.44+15-CA (build 17.0.8+7-LTS)
OpenJDK 64-Bit Server VM Zulu17.44+15-CA (build 17.0.8+7-LTS, mixed mode, sharing)
I had to change a few scripts to add the javascript 5.1 version.
I will test it a bit more on the VM before taking the plunge and upgrading my physical machine.
A big thank you to all involved in the OH project and others for support that I have received over my OH journey from OH2.5 to OH3.4 and now OH4.0