From: thristian@gmail.com   
      
   Package: syncthing   
   Version: 1.29.5~ds1-3   
   Severity: important   
      
   Dear Maintainer,   
      
   Whenever I reboot my Debian system and login, syncthing fails to start   
   automatically. I usually don't notice until a few days later when I notice   
   things haven't been syncing, then I have to remember that I rebooted recently   
   and start it manually. Once started manually, it stays running until the next   
   reboot.   
      
   After failing to start automatically, `systemctl --user status syncthing` says:   
      
   syncthing.service: Scheduled restart job, restart counter is at 4.   
   syncthing.service: Start request repeated too quickly.   
   syncthing.service: Failed with result 'exit-code'.   
   Failed to start syncthing.service - Syncthing - Open Source Continuous File   
   Synchronization.   
      
   Looking a little more deeply with `journalctl --user -t syncthing --boot`, I   
   see messages like this:   
      
   WARNING: Starting API/GUI: listen tcp 127.0.0.1:8384: bind: address already in   
   use   
   WARNING: Starting API/GUI: listen tcp 127.0.0.1:8384: bind: address already in   
   use   
   WARNING: Starting API/GUI: listen tcp 127.0.0.1:8384: bind: address already in   
   use   
   WARNING: Starting API/GUI: listen tcp 127.0.0.1:8384: bind: address already in   
   use   
   WARNING: Starting API/GUI: listen tcp 127.0.0.1:8384: bind: address already in   
   use   
   WARNING: Failed starting API: listen tcp 127.0.0.1:8384: bind: address already   
   in use   
      
   Evidently syncthing can't bind te ports it needs to listen on, it tries several   
   times and fails, then systemd restarts it, and after a few restarts systemd   
   also marks the service as failed.   
      
   This was very puzzling to me because I'd just rebooted - what else could   
   possibly be listening on the syncthing ports? Today I decided to go one step   
   further, and check the system-wide journal too:   
      
   INFO: syncthing v1.29.5 "Gold Grasshopper" (go1.24.9 linux-amd64) debian@debian   
   2025-11-29 20:48:58 UTC   
   INFO: Generating ECDSA key and certificate for syncthing...   
   INFO: Default folder created and/or linked to new config   
   INFO: Default config saved. Edit /run/gdm3/home/gdm-   
   greeter/.local/state/syncthing/config.xml to taste (with Syncthing stopped) or   
   use the GUI   
      
   Apparently what's happening is that after the system boots, the greeter runs   
   under the `gdm3` user, which is apparently counted as a user session, so per-   
   user units like syncthing are started and bind the relevant ports. When I   
   login, that starts a *new* user session, and *another* copy of syncthing, which   
   fails to start because the ports are already bound. Eventually (I'm not sure   
   how) gdm3's copy of syncthing gives up, or is stopped, so days later when I   
   notice the problem I can start syncthing and it works perfectly.   
      
   It would be good if somehow syncthing could be configured to *not* start up for   
   system users like gdm3.   
      
      
   -- System Information:   
   Debian Release: forky/sid   
     APT prefers testing   
     APT policy: (990, 'testing'), (500, 'unstable'), (1, 'experimental')   
   Architecture: amd64 (x86_64)   
   Foreign Architectures: i386   
      
   Kernel: Linux 6.18.5+deb14-amd64 (SMP w/4 CPU threads; PREEMPT)   
   Locale: LANG=en_AU.UTF-8, LC_CTYPE=en_AU.UTF-8 (charmap=UTF-8),    
   ANGUAGE=en_AU:en   
   Shell: /bin/sh linked to /usr/bin/dash   
   Init: systemd (via /run/systemd/system)   
   LSM: AppArmor: enabled   
      
   Versions of packages syncthing depends on:   
   ii  init-system-helpers  1.69   
   ii  libc6                2.42-11+b1   
      
   Versions of packages syncthing recommends:   
   ii  xdg-utils  1.2.1-2   
      
   syncthing suggests no packages.   
      
   -- no debconf information   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)