How to stop NeoForge and mods from updating on startup?

[gregops]

Hi all, after the first successful startup of the MC server container, I'd like to prevent any further NeoForge and mods/packs updates, I'd like it to simply start with the same versions/data as it already has from the first run. I can't find an option to do that though, is that possible?

I.e. stop this from happening when for example the container crashed and is restarted:

[mc-image-helper] 19:02:58.864 INFO  : Re-installing Forge due to version change from MC 1.21.1/Forge 21.1.116 to MC 1.21.1/Forge 21.1.119
[mc-image-helper] 19:02:58.981 INFO  : Running NeoForge 21.1.119 installer for Minecraft 1.21.1. This might take a while...

And similarly with this starting to update all the mods

[mc-image-helper] 19:02:51.411 INFO  : Processing modpack 'All the Mods 10-2.36' (all-the-mods-10) @ 925200:6201429

My compose file is the following:

services:
  mc:
    container_name: mc
    image: itzg/minecraft-server
    tty: true
    stdin_open: true
    ports:
      - "25565:25565"
    environment:
      EULA: "true"
      VERSION: "1.21.1"
      MEMORY: "8G"
      TZ: "Europe/London"
      DIFFICULTY: "easy"
      ALLOW_FLIGHT: "true"
      MAX_PLAYERS: 10
      GUI: "false"
      PVP: "false"
      ONLINE_MODE: "false"
      SERVER_NAME: "My MC Server"
      CF_API_KEY: "<key>"
      TYPE: "AUTO_CURSEFORGE"
      CF_PAGE_URL: https://www.curseforge.com/minecraft/modpacks/all-the-mods-10
      RCON_CMDS_STARTUP: |-
        gamerule drowningDamage false
        gamerule enderPearlsVanishOnDeath false
        gamerule fallDamage false
        gamerule freezeDamage false
        gamerule keepInventory true
        gamerule lavaSourceConversion true
    volumes:
      - ./data-1.21.1-all-the-mods-10:/data

Thanks!

[itzg]

It already does that. You need to pin the version if you don't want it upgrading the modpack unexpectedly.

In the case of NeoForge, noticed it identified a version change:

Re-installing Forge due to version change from MC 1.21.1/Forge 21.1.116 to MC 1.21.1/Forge 21.1.119

[gregops]

Thanks Geoff.

How would I pin the modpack, is it with the CF_FILENAME_MATCHER env variable? I've read the auto-curseforge doc, but can't find anything definitive about pinning overall modpack version, or just stopping modpack updates.

Re NeoForge, yes I see it detected a new version, and that's precisely what I'd like it to stop doing, is there any env variable or other setting that would prevent the version checks, or version upgrades if it still has to do the checks?

I tried cutting off the container's internet access, but then it won't start, it definitely wants to go out to the internet to check for versions, and fails if it can't.

Edit to add - I had the image SHA pinned as well, but that didn't help, I'm assuming NF and modpack versions are resolved dynamically at startup and not associated with container image version.

[itzg]

Yes that is one of three options to use. Refer to the paragraph that starts

The latest file will be located and used by default, but if a specific version is desired you can use one of the following options.

in https://docker-minecraft-server.readthedocs.io/en/latest/types-and-platforms/mod-platforms/auto-curseforge/#usage

[itzg]

Also added a section header

https://docker-minecraft-server.readthedocs.io/en/latest/types-and-platforms/mod-platforms/auto-curseforge/#using-specific-file-version

[gregops]

Thanks for your patience, I get it now. It worked beautifully, pinnning modpack version even downgraded the NeoForge version, and my previously "outdated" clients are able to connect again to the server. My 6-year-old will be very happy when he's back from school.

A small PR updating wording around these things, that I think would've cleared some of my initial confusion - https://github.com/itzg/docker-minecraft-server/pull/3344/files. Feel free to edit further or reject.

Thanks!