Default Persistence does not work

  • Platform information:
    • Hardware: Raspberry Pi 4 Model B Rev 1.4 / 8GB / 256GB SD
    • OS: Raspbian GNU/Linux 10 (buster)
    • Java Runtime Environment: openjdk 11.0.10 2021-01-19 LTS, Zulu11.45+27-CA (build 11.0.10+9-LTS)
    • openHAB version: 3.0.1
  • Issue of the topic: I have two “persistence services” installed - InfluxDB and MapDB
    I have set the InfluxDB as the default “persistence services”.
    But, if I create a new “Item” in the GUI, I still have to add the “Item” to /etc/openhab/persistence/influxdb.persist to make the “Item” create entries in then InfluxDB.

Have I misunderstood the meaning of default “persistence services” or is there something wrong with my openHAB configuration.

This openHAB “installation” is upgraded from a v2 installation to a v3, so I have a mix of Things and Items setup using the configuration files (v2, /etc/openhab/*) and the GUI (v3).


Dan

With “default” it is meant to be the default if you don’t give a persistence service in your rules.
To save the state of your items, you have to specify the item (or group of items) in the influxdb.persist file.

OK, so it was my misunderstanding what “default” does.
Thanks for the clarification.


Dan

That ‘default’ explanation appears not to be the whole truth. I am currently investigating OH3 to upgrade from my existing 2.5.12 installation. I only got a single data point in the rrd4j OH3 UI charts. I have both mapdb and rrd4j persistence in use, each with a .persist file. In my current rules I only use mapdb for persistence calls, so obviously I set the default persistence service to mapdb.
In the debug persistence log I saw that data was being stored to the selected items every minute, but the OH3 UI charts kept showing just a single data point.
Only after setting the default persistence service to ‘rrd4j’ I finally got the UI charts to work (and need to update my rules to explicitly add ‘mapdb’ to the persistence calls)

The documentation also doesn’t mention this and indeed the selection of the default persistence service shouldn’t have an impact on the UI (especially if according to the log the data is actually stored in the rrd4j databases even when mapdb is selected as default). I would call this a bug/shortcoming in the UI…