Krdytkyu

I set up syncthing as a systemd user service on a 16.04 computer. Worked fine. Since I upgraded to 18.04 the service disappears upon reboot.

After rebooting, I see:

$ systemctl --user status syncthing.service 

Unit syncthing.service could not be found.

And syncthing is indeed not running.

Here is ~/.config/systemd/user/syncthing.service (following the example, but note the binary is under my home dir):

[Unit]

Description=Syncthing - Open Source Continuous File Synchronization

Documentation=man:syncthing(1)



[Service]

ExecStart=/home/user/syncthing-prefix/syncthing -no-browser -no-restart -logflags=0

Restart=on-failure

SuccessExitStatus=3 4

RestartForceExitStatus=3 4



[Install]

WantedBy=default.target

I then run this:

$ systemctl --user enable syncthing.service

$ systemctl --user start syncthing.service

Following the setup instructions I used to install the user service originally.

After running the above two commands, I see:

$ systemctl --user status syncthing.service

● syncthing.service - Syncthing - Open Source Continuous File Synchronization

  Loaded: loaded (/home/user/.config/systemd/user/syncthing.service; enabled; 

  Active: active (running) since Tue 2018-11-06 15:28:16 PST; 4s ago

    Docs: man:syncthing(1)

Main PID: 4221 (syncthing)

  CGroup: /user.slice/user-1000.slice/user@1000.service/syncthing.service

          └─4221 /home/user/syncthing-prefix/syncthing -no-b



Nov 06 15:28:18 kind syncthing[4221]: [XXXXX] INFO: Device XXXXXXX-XXXXXXX-XXXXX

Nov 06 15:28:18 kind syncthing[4221]: [XXXXX] INFO: Device XXXXXXX-XXXXXXX-XXXXX

Nov 06 15:28:18 kind syncthing[4221]: [XXXXX] INFO: Device XXXXXXX-XXXXXXX-XXXXX

Nov 06 15:28:18 kind syncthing[4221]: [XXXXX] INFO: GUI and API listening on 127

Nov 06 15:28:18 kind syncthing[4221]: [XXXXX] INFO: Access the GUI via the follo

Nov 06 15:28:18 kind syncthing[4221]: [XXXXX] INFO: Completed initial scan of se

Nov 06 15:28:18 kind syncthing[4221]: [XXXXX] INFO: Completed initial scan of se

Nov 06 15:28:18 kind syncthing[4221]: [XXXXX] INFO: Completed initial scan of se

Nov 06 15:28:19 kind syncthing[4221]: [XXXXX] INFO: Completed initial scan of se

Nov 06 15:28:20 kind syncthing[4221]: [XXXXX] INFO: Completed initial scan of se

as expected. And syncthing then works, as expected, until the next reboot.

Note that I have an encrypted home dir. This was the case when I was using 16.04, too.

It seems you have met a known bug, that can be fixed by changing the order of two lines in /etc/pam.d/common-session from

session optional pam_systemd.so

session optional pam_ecryptfs.so unwrap

to

session optional pam_ecryptfs.so unwrap

session optional pam_systemd.so

Starting the service before login

Since the user directory (where your service is stored) is encrypted before login, this service can't be started before login. Anyway before login (unencryption), syncthing would have nowhere to read/write.

Security warning

This service may let the user home directory unencrypted after the logout (another bug, see this question).

You have the same problem than https://unix.stackexchange.com/q/417162/116970

I would suggest that you add a After= and a Requires= line on your syncthing.service in the [Unit] section so that syncthing is run after the home folder is mounted.

More spefically, you coud try:

[Unit]

Description=Syncthing - Open Source Continuous File Synchronization

Documentation=man:syncthing(1)

After=home-yourusername.mount

Requires=home-yourusername.mount



...

and replace yourusername with your user name