SOLVED: Jellyfin won't restart. core-dump

[Michael Tot Korsgaard]

So today my Jellyfin started to no longer allow me to log in. I realised that this was caused by no more space on the server I increased that, moved my movie library (not installation) to a new folder and softl inked that to the old folder, in order to keep references as they were.

Then I restarted the instance via

Code:

sudo systemctl restart jellyfin

After which my server started responding with a 502 for my jellyfin instance.

Doing a

Code:

sudo systemctl status jellyfin.service

Gives me this:

Code:

× jellyfin.service - Jellyfin Media Server
    Loaded: loaded (/usr/lib/systemd/system/jellyfin.service; enabled; preset: enabled)
    Drop-In: /etc/systemd/system/jellyfin.service.d
            └─jellyfin.service.conf
    Active: failed (Result: core-dump) since Mon 2024-12-23 18:57:22 UTC; 53ms ago
  Duration: 455ms
    Process: 1880814 ExecStart=/usr/bin/jellyfin $JELLYFIN_WEB_OPT $JELLYFIN_FFMPEG_OPT $JELLYFIN_SERVICE_OPT $JELLYFIN_NOWEBAPP_OPT $JELLYFIN_ADDITIONAL_OPTS (code=dumped, signal=ABRT)
  Main PID: 1880814 (code=dumped, signal=ABRT)
        CPU: 341ms

Dec 23 18:57:22 ubuntu-16gb-hel1-2 systemd[1]: jellyfin.service: Scheduled restart job, restart counter is at 5.
Dec 23 18:57:22 ubuntu-16gb-hel1-2 systemd[1]: jellyfin.service: Start request repeated too quickly.
Dec 23 18:57:22 ubuntu-16gb-hel1-2 systemd[1]: jellyfin.service: Failed with result 'core-dump'.
Dec 23 18:57:22 ubuntu-16gb-hel1-2 systemd[1]: Failed to start jellyfin.service - Jellyfin Media Server.

And the log looks like this:

Code:

[2024-12-23 18:57:21.796 +00:00] [INF] Jellyfin version: "10.10.3"
[2024-12-23 18:57:21.815 +00:00] [INF] Environment Variables: ["[JELLYFIN_ADDITIONAL_OPTS, ]", "[JELLYFIN_DATA_DIR, /var/lib/jellyfin]", "[JELLYFIN_CONFIG_DIR, /etc/jellyfin]", "[JELLYFIN_FFMPEG_OPT, --ffmpeg=/usr/lib/jellyfin-ffmpeg/ffmpeg]", "[JELLYFIN_ARGS, $JELLYFIN_WEB_OPT $JELLYFIN_FFMPEG_OPT $JELLYFIN_SERVICE_OPT $JELLYFIN_NOWEBAPP_OPT $JELLFIN_ADDITIONAL_OPTS --datadir $JELLYFIN_DATA_DIR --configdir $JELLYFIN_CONFIG_DIR --logdir $JELLYFIN_LOG_DIR --cachedir $JELLYFIN_CACHE_DIR]", "[JELLYFIN_USER, jellyfin]", "[JELLYFIN_CACHE_DIR, /var/cache/jellyfin]", "[JELLYFIN_WEB_OPT, --webdir=/usr/share/jellyfin/web]", "[JELLYFIN_LOG_DIR, /var/log/jellyfin]"]
[2024-12-23 18:57:21.817 +00:00] [INF] Arguments: ["/usr/lib/jellyfin/bin/jellyfin.dll", "--webdir=/usr/share/jellyfin/web", "--ffmpeg=/usr/lib/jellyfin-ffmpeg/ffmpeg"]
[2024-12-23 18:57:21.818 +00:00] [INF] Operating system: "Ubuntu 24.04.1 LTS"
[2024-12-23 18:57:21.818 +00:00] [INF] Architecture: X64
[2024-12-23 18:57:21.818 +00:00] [INF] 64-Bit Process: True
[2024-12-23 18:57:21.818 +00:00] [INF] User Interactive: True
[2024-12-23 18:57:21.818 +00:00] [INF] Processor count: 8
[2024-12-23 18:57:21.819 +00:00] [INF] Program data path: "/var/lib/jellyfin"
[2024-12-23 18:57:21.819 +00:00] [INF] Log directory path: "/var/log/jellyfin"
[2024-12-23 18:57:21.819 +00:00] [INF] Config directory path: "/etc/jellyfin"
[2024-12-23 18:57:21.819 +00:00] [INF] Cache path: "/var/cache/jellyfin"
[2024-12-23 18:57:21.819 +00:00] [INF] Temp directory path: "/tmp/jellyfin"
[2024-12-23 18:57:21.819 +00:00] [INF] Web resources path: "/usr/share/jellyfin/web"
[2024-12-23 18:57:21.819 +00:00] [INF] Application directory: "/usr/lib/jellyfin/bin/"
[2024-12-23 18:57:21.862 +00:00] [FTL] Unhandled Exception
System.InvalidOperationException: There is an error in XML document (0, 0).
---> System.Xml.XmlException: Root element is missing.
  at System.Xml.XmlTextReaderImpl.Throw(Exception e)
  at System.Xml.XmlTextReaderImpl.ThrowWithoutLineInfo(String res)
  at System.Xml.XmlTextReaderImpl.ParseDocumentContent()
  at System.Xml.XmlReader.MoveToContent()
  at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationReaderMigrationOptions.Read4_MigrationOptions()
  at System.RuntimeMethodHandle.InvokeMethod(Object target, Void** arguments, Signature sig, Boolean isConstructor)
  at System.Reflection.MethodBaseInvoker.InvokeWithNoArgs(Object obj, BindingFlags invokeAttr)
  --- End of inner exception stack trace ---
  at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader, String encodingStyle, XmlDeserializationEvents events)
  at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader)
  at Emby.Server.Implementations.Serialization.MyXmlSerializer.DeserializeFromStream(Type type, Stream stream)
  at Emby.Server.Implementations.Serialization.MyXmlSerializer.DeserializeFromFile(Type type, String file)
  at Jellyfin.Server.Migrations.MigrationRunner.RunPreStartup(ServerApplicationPaths appPaths, ILoggerFactory loggerFactory)
  at Jellyfin.Server.Program.StartApp(StartupOptions options)
  at Jellyfin.Server.Program.<Main>(String[] args)

I'm not good that reading these kind of things and was hoping that someone could help me dechipher it.

My setup:
Ubuntu 24.04.1 LTS running on a Hetzner server.

[TheDreadPirate]

Delete all the XML files in /etc/jellyfin.

[Michael Tot Korsgaard]

Thanks. That solved it after restarting the instance.

Can you explain why that works?

[TheDreadPirate]

One of the XML files in that directory was corrupted or truncated. I can't definitively say why that happens (it's never happened to me), but other users that had this problem USUALLY had their disk fill up at some point.

Deleting those files will trigger Jellyfin to regenerate them with default settings.