[Question] How to use in Portainer Stack

[GudBoiNero]

Hey I seriously love the Minecraft server docker container, I've used it a bunch, but I do always run into the same issue where I have to manually stop the server whenever I want to redeploy or test it, hence why I want to use this.

However here's the thing, I'm doing this all within Portainer, and I'm quite a beginner with Docker so I'm confused as to how I could implement this mc-server-runner with my Portainer stack.

Here is my current stack-

services:
  mc:
    container_name: rlcraft_dregora
    image: itzg/minecraft-server:java8
    stdin_open: true # docker run -i
    tty: true        # docker run -t
    restart: no      # Prevent auto-start
    ports:
      - "43300:25565"
    environment:
      EULA: "TRUE"
      MEMORY: 12G
      TYPE: AUTO_CURSEFORGE
      DEBUG: "true"
      VERSION: 1.12.2
      CF_PAGE_URL: "https://www.curseforge.com/minecraft/modpacks/rlcraft-dregora/files/5861566"
    volumes:
      - mc_forge:/data
      - ./mods:/mods:ro
  
  scheduler:
    image: ubuntu:latest
    container_name: minecraft_scheduler
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock # Allow scheduler to control Docker
    command: >
      bash -c "
      apt-get update &&
      apt-get install -y cron docker.io &&
      echo '0 0 * * 6 docker start rlcraft_dregora' > /etc/cron.d/minecraft-scheduler &&
      echo '0 0 * * 1 docker stop rlcraft_dregora' >> /etc/cron.d/minecraft-scheduler &&
      chmod 0644 /etc/cron.d/minecraft-scheduler &&
      crontab /etc/cron.d/minecraft-scheduler &&
      cron -f"
    restart: unless-stopped

volumes:
  # declared the named volume, but use default/local storage engine
  mc_forge: {}

I've got a fun little use case where I'm using a cron job to allow the server only to run while it's a weekend! It works, well, if you ignore the fact that I can't actually stop the server to begin with.

So I stumbled across this repository and figured it would be exactly what I needed!

I'm just a little stumbled as to how exactly I should implement this into my stack. I would prefer if it was something I could do in the stack file, but I figure that would make things more complicated, I would just like some help figuring out possible ways to use the wrapper for this server.

Thanks!

[itzg]

The itzg/minecraft-server image is already using mc-server-runner. That's why I implemented it 😄

It already initiates a graceful server shutdown when docker sends the stop signal. If yours it not stopping gracefully then it is likely an issue caused by one or more mods.

FYI

https://github.com/itzg/docker-minecraft-server/blob/0582a8ab97d68bca297bca555ebb46c4337afeb4/scripts/start-finalExec#L360

[GudBoiNero]

How could I debug it to see what I could do to fix it? I've tried this in the past with other mods and it's never worked before.

[GudBoiNero]

services:
  minecraft:
    image: itzg/minecraft-server:latest
    container_name: minecraft
    ports:
      - "25565:25565"
    environment:
      EULA: "TRUE" # Accept the Minecraft EULA
      MEMORY: "2G" # Adjust based on your system's memory
    volumes:
      - minecraft_data:/data
    restart: unless-stopped

volumes:
  minecraft_data:

I just made a tiny example with no mods. It gives me code: 500 whenever I try to stop or restart the container.

I noticed that when i try to shut my vm down the process blocking it from shutting down is actually the mc-server-runner instance

[itzg]

Please provide container logs during shutdown/stop. Use docker stop to cross check behavior. If you're troubleshooting an issue during system shutdown then that could be any number of other things.

[GudBoiNero]

Dec 14 23:01:51 ubuntu-server dockerd[1202]: time="2024-12-14T23:01:51.338741580Z" level=info msg="No non-localhost DNS nameservers are left in resolv.conf. Using default external servers"
Dec 14 23:01:53 ubuntu-server dockerd[1202]: time="2024-12-14T23:01:53.409046886Z" level=info msg="ignoring event" container=6a3b1cbe611f436b4bca27f497a9c886b9bd95dd43e420af2147bb1b771961bd module=libcontainerd namespace=moby topic=/tasks/delete type="*events.TaskDelete"
Dec 14 23:02:53 ubuntu-server dockerd[1202]: time="2024-12-14T23:02:53.505766210Z" level=info msg="No non-localhost DNS nameservers are left in resolv.conf. Using default external servers"
Dec 14 23:02:55 ubuntu-server dockerd[1202]: time="2024-12-14T23:02:55.528701758Z" level=info msg="ignoring event" container=6a3b1cbe611f436b4bca27f497a9c886b9bd95dd43e420af2147bb1b771961bd module=libcontainerd namespace=moby topic=/tasks/delete type="*events.TaskDelete"
Dec 14 23:03:55 ubuntu-server dockerd[1202]: time="2024-12-14T23:03:55.617352861Z" level=info msg="No non-localhost DNS nameservers are left in resolv.conf. Using default external servers"
Dec 14 23:03:57 ubuntu-server dockerd[1202]: time="2024-12-14T23:03:57.631419232Z" level=info msg="ignoring event" container=6a3b1cbe611f436b4bca27f497a9c886b9bd95dd43e420af2147bb1b771961bd module=libcontainerd namespace=moby topic=/tasks/delete type="*events.TaskDelete"
Dec 14 23:04:57 ubuntu-server dockerd[1202]: time="2024-12-14T23:04:57.720270565Z" level=info msg="No non-localhost DNS nameservers are left in resolv.conf. Using default external servers"
Dec 14 23:04:59 ubuntu-server dockerd[1202]: time="2024-12-14T23:04:59.847956326Z" level=info msg="ignoring event" container=6a3b1cbe611f436b4bca27f497a9c886b9bd95dd43e420af2147bb1b771961bd module=libcontainerd namespace=moby topic=/tasks/delete type="*events.TaskDelete"

Tried to stop the container three times. Gave me error 500 each time. Guess it's ignoring the TaskDelete task?

[itzg]

Please provide the container logs, which will show what the Minecraft server is doing along with the stop command sent to it.

[GudBoiNero]

Oops didn't realize that's what you meant. My logs aren't showing any signs of a command being sent.

[init] Running as uid=1000 gid=1000 with /data as 'drwxr-x--- 7 1000 1000 4096 Dec 14 16:56 /data'
[init] Resolving type given VANILLA
[init] Resolved version given LATEST into 1.21.4
[mc-image-helper] 22:47:57.419 INFO  : Created/updated 1 property in /data/server.properties
[init] Setting initial memory to 2G and max to 2G
[init] Starting the Minecraft server...
Starting net.minecraft.server.Main
[22:48:04] [ServerMain/INFO]: Environment: Environment[sessionHost=https://sessionserver.mojang.com, servicesHost=https://api.minecraftservices.com, name=PROD]
[22:48:05] [ServerMain/INFO]: Loaded 1370 recipes
[22:48:05] [ServerMain/INFO]: Loaded 1481 advancements
[22:48:05] [Server thread/INFO]: Starting minecraft server version 1.21.4
[22:48:05] [Server thread/INFO]: Loading properties
[22:48:05] [Server thread/INFO]: Default game type: SURVIVAL
[22:48:05] [Server thread/INFO]: Generating keypair
[22:48:05] [Server thread/INFO]: Starting Minecraft server on *:25565
[22:48:05] [Server thread/INFO]: Using epoll channel type
[22:48:05] [Server thread/INFO]: Preparing level "world"
[22:48:05] [Server thread/INFO]: Preparing start region for dimension minecraft:overworld
[22:48:06] [Worker-Main-6/INFO]: Preparing spawn area: 0%
[22:48:06] [Worker-Main-6/INFO]: Preparing spawn area: 0%
[22:48:06] [Worker-Main-2/INFO]: Preparing spawn area: 51%
[22:48:07] [Worker-Main-6/INFO]: Preparing spawn area: 51%
[22:48:07] [Worker-Main-7/INFO]: Preparing spawn area: 51%
[22:48:08] [Worker-Main-3/INFO]: Preparing spawn area: 51%
[22:48:08] [Server thread/INFO]: Time elapsed: 2736 ms
[22:48:08] [Server thread/INFO]: Done (2.984s)! For help, type "help"
[22:48:08] [Server thread/INFO]: Starting remote control listener
[22:48:08] [Server thread/INFO]: Thread RCON Listener started
[22:48:08] [Server thread/INFO]: RCON running on 0.0.0.0:25575
[22:49:08] [Server thread/INFO]: Server empty for 60 seconds, pausing

[itzg]

In that case it must be an issue with docker.

[GudBoiNero]

Hey so I ended up figuring it out. Turns out it was not the mc-server's running which honestly I'm not surprised about cuz I didn't see anyone else having a similar issue.

It seemed to be an issue of an apt installation and a snap installation of docker conflicting with each other on my ubuntu vm. The issue was not apparmor like the title says, I just had to fully purge the snap installation of docker and then reboot for it to fix itself. But I had to verify I had a valid installation via apt using apt search docker-ce.

Hence the graceful shutdown 💯

[02:19:13] [Worker-Main-4/INFO]: Preparing spawn area: 2%
[02:19:13] [Worker-Main-7/INFO]: Preparing spawn area: 2%
[02:19:14] [Worker-Main-4/INFO]: Preparing spawn area: 18%
[02:19:15] [Worker-Main-1/INFO]: Preparing spawn area: 32%
[02:19:15] [Worker-Main-6/INFO]: Preparing spawn area: 51%
[02:19:15] [Server thread/INFO]: Time elapsed: 2145 ms
[02:19:15] [Server thread/INFO]: Done (4.326s)! For help, type "help"
[02:19:15] [Server thread/INFO]: Starting remote control listener
[02:19:15] [Server thread/INFO]: Thread RCON Listener started
[02:19:15] [Server thread/INFO]: RCON running on 0.0.0.0:25575
2024/12/15 02:19:33 Stopping with rcon-cli
[02:19:33] [RCON Listener #1/INFO]: Thread RCON Client /0:0:0:0:0:0:0:1 started
[02:19:33] [Server thread/INFO]: [Rcon: Stopping the server]
[02:19:33] [RCON Client /0:0:0:0:0:0:0:1 #2/INFO]: Thread RCON Client /0:0:0:0:0:0:0:1 shutting down
2024-12-15T02:19:33.906Z	INFO	mc-server-runner	Waiting for completion...
[02:19:33] [Server thread/INFO]: Stopping server
[02:19:33] [Server thread/INFO]: Saving players
[02:19:33] [Server thread/INFO]: Saving worlds
[02:19:34] [Server thread/INFO]: Saving chunks for level 'ServerLevel[world]'/minecraft:overworld