Jellyfin Migration Failed: 'UserData' Tracking Error Fix

Hey there, fellow media server enthusiasts! Have you ever hit that dreaded Jellyfin migration failed wall, especially when upgrading from an older version like 10.10.7 to 10.11.4? It's a real head-scratcher when your server refuses to start, throwing an error about 'UserData' already being tracked. Trust me, guys, you're not alone! This specific Jellyfin migration problem can be incredibly frustrating, leaving your perfectly curated media library in limbo. The error message, "The instance of entity type 'UserData' cannot be tracked because another instance with the same key value for {'ItemId', 'UserId', 'CustomDataKey'} is already being tracked," points directly to an underlying database conflict, usually within your library.db file. It's like trying to move house, but two identical boxes are labeled with the exact same contents and destination, causing a system-wide jam. This article is your ultimate guide to troubleshooting and fixing this perplexing Jellyfin upgrade issue, ensuring a smooth transition to Jellyfin 10.11.4. We're going to dive deep into understanding what causes this UserData tracking error, how to prepare your system for a successful migration, and most importantly, provide you with clear, step-by-step instructions to resolve these database conflicts and get your Jellyfin server up and running again. Whether you're running Jellyfin on TrueNAS Scale using YAML configurations, or any other Dockerized environment, the core principles of resolving this database integrity issue remain the same. So, grab a coffee, and let's get your media server back on track, thriving on the latest and greatest Jellyfin version!

Understanding the Jellyfin Migration Headache: The 'UserData' Tracking Error

Alright, let's break down this pesky Jellyfin migration headache, specifically that 'UserData' tracking error that brought your upgrade process to a screeching halt. When Jellyfin tries to upgrade its internal database, especially from an older version like 10.10.7 to 10.11.4, it performs a series of migrations. One crucial step involves moving and updating UserData entries. This UserData isn't just some generic data; it's the heart and soul of your personalized media experience. We're talking about things like playback progress, watched status, ratings, favorites, and any custom data you might have associated with your media items. Each piece of UserData is uniquely identified by a combination of ItemId (which specific movie or episode), UserId (which user account), and sometimes a CustomDataKey for more granular information. The error message, "The instance of entity type 'UserData' cannot be tracked because another instance with the same key value for {'ItemId', 'UserId', 'CustomDataKey'} is already being tracked," essentially means that during this migration, the database engine (Entity Framework Core, in Jellyfin's case) encountered two or more identical entries for these crucial key values. It's like having two identical keys trying to open the same lock – the system gets confused and refuses to proceed because it expects each instance of UserData to be unique based on these three identifiers. This isn't necessarily a bug in the new version, but rather an inconsistency or corruption that might have developed in your library.db over time while running version 10.10.7. Possible causes include previous interrupted database operations, power outages, software crashes, or even a subtle bug in how older Jellyfin versions handled database writes under specific circumstances. The migration routine tries to ensure data integrity by not allowing duplicate unique keys, and when it hits one, it throws this InvalidOperationException. The log entry, "Tried to find user with index '19' but there are only '15' users," is a major clue here, indicating that some UserData entries might be referencing user IDs that no longer exist or are out of sync with your actual user accounts in users.db. This specific inconsistency is often the root cause of the UserData tracking conflict, as the migration process struggles to reconcile data for ghost users or incorrectly indexed entries. Understanding this underlying mechanism is the first step towards a targeted and effective fix for your Jellyfin upgrade woes.

Pre-Migration Checkup: Essential Steps Before You Upgrade Jellyfin

Before we dive headfirst into fixing the 'UserData' tracking error, let's talk about the absolute most crucial step in any significant Jellyfin migration, especially from 10.10.7 to 10.11.4: a proper pre-migration checkup. Guys, I cannot stress this enough – backups are paramount! Think of it as putting on your seatbelt before a road trip; you hope you don't need it, but you'll be eternally grateful if you do. For your Jellyfin server, this means thoroughly backing up your entire Jellyfin data directory. The key files you absolutely need to safeguard are library.db and users.db, as these contain all your media metadata, user profiles, and that pesky UserData we're wrestling with. If you're running on a platform like TrueNAS Scale, you're in luck! Leverage its robust snapshot capabilities for your Jellyfin datasets. Creating a snapshot before you even think about initiating the upgrade will give you an instant, revertible point in time if anything goes sideways. Beyond snapshots, consider copying the entire Jellyfin config folder to a separate, safe location. This redundancy is your best friend. Next up, let's look at your environment. You mentioned running Jellyfin in Docker via a YAML configuration on TrueNAS Scale. Before updating your YAML file to point to the new 10.11.4 image, make sure your existing 10.10.7 instance is completely shut down. An unclean shutdown or background processes could potentially leave your database in an inconsistent state, which we definitely want to avoid. While we're talking about Docker, double-check your volume mounts to ensure that the data directory is correctly persisted and accessible. Issues with file permissions or incorrect paths can also lead to migration failures, though less directly related to the UserData error. Also, take note of your extensive list of plugins (Ani-Sync, AniDB, AniList, Artwork, OMDb, TMDb, etc.). While plugins rarely cause direct database migration issues, a large number of them can sometimes contribute to resource contention or reveal underlying database inefficiencies during heavy operations. Although we won't directly blame them for the UserData issue, keeping a list of your installed plugins is good practice. Finally, remember that jumping from 10.10.7 to 10.11.4 is a minor version upgrade, but still involves significant database schema changes. A thorough backup ensures that you can always revert to your stable 10.10.7 instance if our troubleshooting steps don't immediately resolve the issue. Don't skip these critical pre-migration steps; they're your safety net!

Step-by-Step Fix: Resolving the 'UserData' Tracking Conflict

Alright, guys, this is where the rubber meets the road! We're diving into the nitty-gritty of resolving that infuriating 'UserData' tracking conflict that's preventing your Jellyfin migration from 10.10.7 to 10.11.4. This process requires a bit of courage and careful database manipulation, but armed with the right tools and knowledge, you'll sail through it. Remember that pre-migration backup we talked about? Now's the time it truly shines. If you mess up, you can always revert. Our goal here is to carefully identify and eliminate the duplicate or ghost UserData entries that are causing the System.InvalidOperationException and the migration failure. The key is to understand that Jellyfin's database, library.db, is a SQLite database, which is incredibly accessible and manageable. We'll be using specific tools and focusing on the clues provided by your logs to pinpoint the exact problem areas. This section will walk you through identifying the culprits, cleaning them up, and then re-attempting your migration. Patience and precision are your allies here, so let's get to work and get your Jellyfin server upgraded and running smoothly!

Identifying the Culprit: Examining Your Jellyfin Database

To really get to the bottom of this 'UserData' tracking error during your Jellyfin migration, we need to roll up our sleeves and peek inside your library.db file. This is where the problematic entries are hiding, and we'll use a fantastic, free tool called DB Browser for SQLite (or any similar SQLite editor) to uncover them. First, ensure your Jellyfin server is completely stopped. This is vital to prevent any writes to the database while we're examining and modifying it. Next, locate your library.db file within your Jellyfin data directory (e.g., /config/data/library.db if you're in a Docker container or on TrueNAS Scale). Copy this library.db file to a safe place on your local machine before opening it with DB Browser for SQLite. This serves as an additional layer of backup for our operations. Once opened, navigate to the Browse Data tab and select the UserData table. This table is where all those personalized user interactions with your media are stored. The error message explicitly points to conflicts involving {'ItemId', 'UserId', 'CustomDataKey'}. These are the columns you need to focus on. Sort the table by ItemId, then UserId, and finally CustomDataKey. As you scroll through, you're looking for rows where all three of these values are identical. These are your duplicate entries, and they are precisely what's throwing off the migration. However, remember that critical log message: "Tried to find user with index '19' but there are only '15' users." This is a massive clue. It suggests that some UserData entries might be associated with UserIds that either no longer exist in your users.db or have become out of sync due to prior database inconsistencies or user deletions. To verify this, you'll also need to open your users.db file (found in the same Jellyfin data directory) and look at its Users table to see the actual valid Ids of your current users. Compare the UserId values in the UserData table of library.db with the Ids in the Users table of users.db. If you find any UserId in UserData that does not correspond to an existing user in users.db (e.g., UserId = 19 when your users.db only lists users up to Id = 15), you've found a ghost user entry. These ghost entries are often the root cause of the migration failure, as the migration routine tries to process data for non-existent users, leading to tracking conflicts. By meticulously examining these tables, sorting by the key columns, and cross-referencing user IDs, you can accurately identify the specific rows that are causing your Jellyfin server's upgrade process to halt. This diagnostic step is absolutely essential for a targeted and effective resolution.

The Clean-Up Crew: Strategies to Resolve Conflicts

Now that you've meticulously identified the problematic UserData entries in your library.db, it's time to bring in the clean-up crew and resolve those conflicts to allow your Jellyfin migration from 10.10.7 to 10.11.4 to finally complete. This part requires careful execution, so always double-check your work! Still with DB Browser for SQLite and your Jellyfin server stopped, navigate back to the UserData table in library.db. Based on our previous identification, we have two primary types of issues: true duplicate entries (where ItemId, UserId, and CustomDataKey are identical for multiple rows) and ghost user entries (where UserId refers to a non-existent user). Let's tackle them strategically. For true duplicate entries, you need to decide which one to keep. Often, there might be a DateCreated or LastUpdated column that can help you determine the most recent or valid entry. If such columns exist, keep the latest one and delete the older duplicates. If you're unsure or there's no clear indicator, and you're comfortable losing a bit of specific playback progress for that item/user combination, you might delete all but one. Remember, you're looking for exact matches across ItemId, UserId, and CustomDataKey. However, the more critical issue based on your logs (Tried to find user with index '19' but there are only '15' users) points to ghost user entries. These are entries in the UserData table where the UserId value points to a user that no longer exists in your users.db file. To resolve this, identify all rows in the UserData table that have a UserId that is not present in the Users table of your users.db. For instance, if your users.db only has users with IDs from 1 to 15, any UserData entry with UserId = 19 (or any other ID outside this valid range) is a ghost entry. These rows must be deleted. Select all such rows in DB Browser for SQLite and hit the 'Delete Record' button. This step is usually the most effective fix for the specific error message you're receiving, as it removes data that the migration routine cannot reconcile with actual users. After making all your deletions (be absolutely sure you're deleting the correct rows!), it's crucial to commit your changes. In DB Browser for SQLite, look for the 'Write Changes' button (it usually looks like a floppy disk icon). Clicking this will permanently save your modifications to library.db. If you close the program without committing, your changes will be lost. As a more drastic measure, if you're okay with losing all user playback data and watched status (e.g., if your library is small or you prefer a fresh start for user data), you could entirely clear the UserData table. However, this is a last resort and typically overkill for the specific error at hand. Focus on removing the duplicates and ghost user entries first. Once library.db is cleaned and changes are committed, you've removed the specific impediments to your Jellyfin migration.

Executing the Migration: Re-attempting the Upgrade

With your library.db meticulously cleaned and those pesky UserData conflicts resolved, it's finally time to re-attempt your Jellyfin migration from 10.10.7 to 10.11.4! This step should feel much smoother now that the underlying database issues have been addressed. First and foremost, ensure that Jellyfin remains completely stopped if it isn't already. Any attempt to start it before the migration would just trigger the same error with your still-old library.db structure. Next, if you're running Jellyfin on TrueNAS Scale via a YAML configuration (as indicated in your environment), you'll need to update your YAML file. Change the Docker image tag from your old version (e.g., jellyfin/jellyfin:10.10.7) to the new one you wish to upgrade to (e.g., jellyfin/jellyfin:10.11.4 or jellyfin/jellyfin:latest if you want the very newest stable). Save your updated YAML file. Now, apply this new configuration within TrueNAS Scale, which will instruct Docker to pull the new Jellyfin image and attempt to start the container. As Jellyfin begins to boot with the new version, it will detect that the library.db is from an older schema and will automatically initiate the migration process. This is the moment of truth! You'll want to monitor your Jellyfin logs very closely during this startup phase. Instead of the InvalidOperationException about UserData, you should now see a series of INF (information) messages detailing the migration steps. Look for messages like `Perform migration