Openhab service does not start anymore

I got a pine64 with pre-installed openhab.
Openhab installation is in /opt/openhab
It was running o.k. and the service started correctly.
Since two days ago the service exited with an error:
I did not update or change anything recently.
However it still starts correctly if I start it with /opt/openhab/start.sh
Weird because everything looks o.k.

Rainer

Blockquote
sudo service openhab status
● openhab.service - The openHAB 2 Home Automation Bus Solution
Loaded: loaded (/lib/systemd/system/openhab.service; enabled; vendor preset: enabled)
Active: inactive (dead) (Result: exit-code) since Tue 2018-07-24 20:35:00 CEST; 14min ago
Docs: http://docs.openhab.org
Process: 2408 ExecStop=/bin/kill -SIGINT $MAINPID (code=exited, status=0/SUCCESS)
Process: 2320 ExecStart=/opt/openhab/start.sh server (code=exited, status=127)
Main PID: 2320 (code=exited, status=127)

Jul 24 20:35:00 openhab systemd[1]: openhab.service: Unit entered failed state.
Jul 24 20:35:00 openhab systemd[1]: openhab.service: Failed with result ‘exit-code’.
Jul 24 20:35:00 openhab systemd[1]: openhab.service: Service hold-off time over, scheduling restart.
Jul 24 20:35:00 openhab systemd[1]: Stopped The openHAB 2 Home Automation Bus Solution.
Jul 24 20:35:00 openhab systemd[1]: openhab.service: Start request repeated too quickly.
Jul 24 20:35:00 openhab systemd[1]: Failed to start The openHAB 2 Home Automation Bus Solution.

Blockquote

/lib/systemd/system/openhab.service looks o.k.

Blockquote
[Unit]
Description=The openHAB 2 Home Automation Bus Solution
Documentation=http://docs.openhab.org
Wants=network-online.target
After=network-online.target

[Service]
Type=simple
User=openhab
Group=openhab
GuessMainPID=yes
WorkingDirectory=/opt/openhab
#EnvironmentFile=/etc/default/openhab
ExecStart=/opt/openhab/start.sh server
ExecStop=/bin/kill -SIGINT $MAINPID
Restart=on-failure

[Install]
WantedBy=multi-user.target

Blockquote

If you run a SD card only config, I would suspect the SD card. These cards were never meant as a computer storage device and will wear out pretty fast if used to run applications with a lot of I/O.

SOLVED
journalctl -u openhab.service showed the following error
/usr/bin/java: error while loading shared libraries: libjli.so
-> I just overwrote the java installation by the same (I even used the same tgz file I used for the previous installation.
–> the service starts now
The weird thing is that it started without errors before when I started it with ./start.sh.