How to delete persistence items and data

I’m running openHAB 3.2.0.M3 on RaspberryPI with rrd4j persistence

Beginning with OH2 I had a lot of items defined by item files. In the meantime these items are no longer used and they are no longer in any item file on my system.
But I detected a lot of rrd-files belonging to these old items. So I decided to throw them away.

But how shall I do it ?
I thought the REST API has a solution : “Delete item data from a specific persistence service”
The problem might be the start and endtime string…
I tried startime string “2020-10-27’T’20:10:00.000Z” endtime string “2021-10-27’T’20:10:00.000Z”

The resulting URL shows me this:

But Server response is:

Error : Bad Request
Response body

  "error": {
    "message": "Persistence service not modifiable: rrd4j",
    "http-code": 400

I did not find any hint to fill in the start and endtime fields in any other, the correct way.

So I need some help

In OH 3 each Item generates it’s own rrd file under $OH_USERDATA/persistence/rrd4j. I think you just simply need to delete the file with the name corresponding to the Item that no longer exists.

You probably don’t want to do this while openHAB is running though.

Once the rrd file are gone, so is all the data for that Item.

Thank you Rich, I didn’t think that it’s so easy !