Oh2 stopped logging - what went wrong?

Setup, Configuration and Use Runtime
1
  • Platform information:
    • Hardware: Raspberry Pi 3
    • OS: raspbian 4.9.35-v7+
    • Java Runtime Environment: openjdk version "1.8.0_121" OpenJDK Runtime Environment (Zulu Embedded 8.20.0.42-linux-aarch32hf) (build 1.8.0_121-b42) OpenJDK Client VM (Zulu Embedded 8.20.0.42-linux-aarch32hf) (build 25.121-b42, mixed mode, Evaluation)
    • openHAB version: 2.1.0-1 (Release Build) - openHabian 1.3
  • Issue of the topic: OH2 stopped logging (events.log and openhab.log)
  • Please post configurations (if applicable): * n/a
  • If logs where generated please post these here using code fences: none

three days ago, openHAB2 stopped logging events and system logs. openHAB itself is still up and running with everything working as intended (including rules, persistance and all). There’s no error or something suspicious in either openHAB logs or system logs. There’s enough space left for the logfiles, they just stopped working.
I didn’t change anything regarding logging, last changes were some rules…

What baffles me are the rights on /var/log/openhab.log and ../events.log. They changed to “openhabian” - including events.log.1. But still: Events.log filled for another ~5hours…?

after chowning the files to openhab again, logging now works. But how did the ownership change in the first place? Certainly not with a action from me!?