Server keeps resetting config files when started

[krankydonkey]

Describe the problem

If I stop the container to make changes to the paper-global.yml or ops.json, these will get overwritten to the default files again when I next start the server.

Container definition

Deployed with podman via systemd. Contents of ~/.config/containers/systemd/paper.container :

[Container]
AutoUpdate=registry
ContainerName=paper
Image=docker.io/itzg/minecraft-server
EnvironmentFile=paper.env
PublishPort=25565:25565
Volume=/home/minecraft/data:/data
UserNS=keep-id

[Install]
WantedBy=default.target

Container logs

[09:30:50] [ServerMain/INFO]: [bootstrap] Running Java 21 (OpenJDK 64-Bit Server VM 21.0.7+6-LTS; Eclipse Adoptium Temurin-21.0.7+6) on Linux 6.8.0-60-generic (amd64)
[09:30:50] [ServerMain/INFO]: [bootstrap] Loading Paper 1.21.4-231-ver/1.21.4@09e9afd (2025-05-19T17:59:36Z) for Minecraft 1.21.4
[09:30:51] [ServerMain/INFO]: [PluginInitializerManager] Initializing plugins...
[09:30:51] [ServerMain/INFO]: [PluginInitializerManager] Initialized 0 plugins
[09:30:53] [ServerMain/INFO]: Environment: Environment[sessionHost=https://sessionserver.mojang.com, servicesHost=https://api.minecraftservices.com, name=PROD]
[09:30:54] [ServerMain/INFO]: Loaded 1370 recipes
[09:30:54] [ServerMain/INFO]: Loaded 1481 advancements
[09:30:54] [ServerMain/INFO]: [MCTypeRegistry] Initialising converters for DataConverter...
[09:30:54] [ServerMain/INFO]: [MCTypeRegistry] Finished initialising converters for DataConverter in 110.5ms
[09:30:54] [Server thread/INFO]: Starting minecraft server version 1.21.4
[09:30:54] [Server thread/INFO]: Loading properties
[09:30:54] [Server thread/INFO]: This server is running Paper version 1.21.4-231-ver/1.21.4@09e9afd (2025-05-19T17:59:36Z) (Implementing API version 1.21.4-R0.1-SNAPSHOT)
[09:30:54] [Server thread/INFO]: [spark] This server bundles the spark profiler. For more information please visit https://docs.papermc.io/paper/profiling
[09:30:54] [Server thread/INFO]: Server Ping Player Sample Count: 12
[09:30:54] [Server thread/INFO]: Using 4 threads for Netty based IO
[09:30:54] [Server thread/INFO]: [MoonriseCommon] Paper is using 3 worker threads, 1 I/O threads
[09:30:54] [Server thread/INFO]: [ChunkTaskScheduler] Chunk system is using population gen parallelism: true
[09:30:55] [Server thread/INFO]: Default game type: SURVIVAL
[09:30:55] [Server thread/INFO]: Generating keypair
[09:30:55] [Server thread/INFO]: Starting Minecraft server on *:25565
[09:30:55] [Server thread/INFO]: Using epoll channel type
[09:30:55] [Server thread/INFO]: Paper: Using libdeflate (Linux x86_64) compression from Velocity.
[09:30:55] [Server thread/INFO]: Paper: Using OpenSSL 3.x.x (Linux x86_64) cipher from Velocity.
[09:30:55] [Server thread/INFO]: Server permissions file permissions.yml is empty, ignoring it
[09:30:55] [Server thread/INFO]: Preparing level "world"
[09:30:55] [Server thread/INFO]: Preparing start region for dimension minecraft:overworld
[09:30:55] [Server thread/INFO]: Preparing spawn area: 0%
[09:30:55] [Server thread/INFO]: Time elapsed: 382 ms
[09:30:55] [Server thread/INFO]: Preparing start region for dimension minecraft:the_nether
[09:30:55] [Server thread/INFO]: Preparing spawn area: 0%
[09:30:55] [Server thread/INFO]: Time elapsed: 100 ms
[09:30:55] [Server thread/INFO]: Preparing start region for dimension minecraft:the_end
[09:30:55] [Server thread/INFO]: Preparing spawn area: 0%
[09:30:56] [Server thread/INFO]: Time elapsed: 41 ms
[09:30:56] [Server thread/INFO]: [spark] Starting background profiler...
[09:30:56] [Server thread/INFO]: Done preparing level "world" (0.920s)
[09:30:56] [Server thread/INFO]: Starting remote control listener
[09:30:56] [Server thread/INFO]: Thread RCON Listener started
[09:30:56] [Server thread/INFO]: RCON running on 0.0.0.0:25575
[09:30:56] [Server thread/INFO]: Running delayed init tasks
[09:30:56] [Server thread/INFO]: Done (5.673s)! For help, type "help"

[itzg]

What's in paper.env

[krankydonkey]

EULA=true
TYPE=PAPER
VERSION=1.21.4
MEMORY=4G

[itzg]

Take a look at

https://docker-minecraft-server.readthedocs.io/en/latest/configuration/server-properties/#opadministrator-players

You could set EXISTING_OPS_FILE to "SKIP", but that's unlikely to be an issue since you're not settings OPS.

As for any other files, such as paper config, those aren't directly managed by the image so I can't help with that.

[krankydonkey]

Im not really sure what to do about that, as starting a paper server manually doesn't seem to overwrite files.

It's got nothing to do with these lines 49-51 in https://github.com/itzg/docker-minecraft-server/blob/master/scripts/start-deployPaper ?

Download default configs to allow for consistent patching

DOWNLOAD_DEFAULT_CONFIGS=$(buildDownloadList "$PAPER_CONFIG_DEFAULTS_REPO" "$VERSION" paper-global.yml paper-world-defaults.yml)
export DOWNLOAD_DEFAULT_CONFIGS

[itzg]

It skips existing files

docker-minecraft-server/scripts/start-setupEnvVariables

Line 34 in 1370f58

--skip-existing --skip-up-to-date=false \

Set the env var DEBUG to "true" and provide the full startup logs if you want to confirm further.

[krankydonkey]

setting DEBUG=true didn't give any extra output in the log file

I also tried setting the PAPER_CONFIG_REPO variable and that seems to do nothing as well
The .env file is clearly getting processed though as the uid's match the user and the ops file is updated by the OPS variable

[trashforreal]

i am in the same boat. happening to one of the mod's config file

[itzg]

setting DEBUG=true didn't give any extra output in the log file

It's not applying your container changes then. There is significantly more container log output during the init stage with that enabled. I can them further without those logs.

[itzg]

i am in the same boat. happening to one of the mod's config file

@trashforreal provide the same debug logs I am requesting of @krankydonkey

[itzg]

For both, I mean the logs shown by docker logs and not the log file within the data directory. And make sure you're setting

DEBUG=true

in paper.env and reapplying those changes however that works with systemd