installing forge 1.12.2 via portainer

[DevDroid1]

hey i am trying to use docker to add a minecraft server container to my Synology NASand I specifically need version 1.12.2 with forge installed however I am unsure how to stop it from auto-updating to the latest version I really need this soon for an event and I can't find any answers online that show how to do it on portainer any suggestion please add web script if you have figured it out

for reference the current script I m using is the following
version: "3.8"
services:
minecraft:
image: itzg/minecraft-server
container_name: minecraftjava
environment:
- UID=1024
- GID=100
- TYPE=FORGE
- SERVER_NAME=HDROIDSERVER
- JVM_XX_OPTS=-XX:+UseG1GC -XX:+ParallelRefProcEnabled -XX:MaxGCPauseMillis=200 -XX:+UnlockExperimentalVMOptions -XX:+DisableExplicitGC -XX:+AlwaysPreTouch -XX:G1HeapWastePercent=5 -XX:G1MixedGCCountTarget=4 -XX:G1MixedGCLiveThresholdPercent=90 -XX:G1RSetUpdatingPauseTimePercent=5 -XX:SurvivorRatio=32 -XX:+PerfDisableSharedMem -XX:MaxTenuringThreshold=1 -XX:G1NewSizePercent=30 -XX:G1MaxNewSizePercent=40 -XX:G1HeapRegionSize=8M -XX:G1ReservePercent=20 -XX:InitiatingHeapOccupancyPercent=15
- MAX_MEMORY=8G
- EULA=TRUE
volumes:
- /volume1/docker/minecraftjava:/data:rw
network_mode: host
restart: always

[itzg]

Set and pin the Minecraft version (1.12.2) with VERSION env var

https://docker-minecraft-server.readthedocs.io/en/latest/versions/minecraft/

Can pin Forge version with FORGE_VERSION env var if needed

https://docker-minecraft-server.readthedocs.io/en/latest/types-and-platforms/server-types/forge/

[DevDroid1]

that resolved the problem that i had itzg

however now it can not get past the starting sequence on portainer
if I look at my logs it seems to keep repeating the same actions and I end up with a last output of
failed to ping localhost:25565 : could not connect to Minecraft server: dial tcp [::1]:25565: connect: connection refused

here are my logs as I said they keep repeating
A problem occurred running the Server launcher.java.lang.reflect.InvocationTargetException
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.base/java.lang.reflect.Method.invoke(Unknown Source)
at net.minecraftforge.fml.relauncher.ServerLaunchWrapper.run(ServerLaunchWrapper.java:70)
at net.minecraftforge.fml.relauncher.ServerLaunchWrapper.main(ServerLaunchWrapper.java:34)
Caused by: java.lang.ClassCastException: class jdk.internal.loader.ClassLoaders$AppClassLoader cannot be cast to class java.net.URLClassLoader (jdk.internal.loader.ClassLoaders$AppClassLoader and java.net.URLClassLoader are in module java.base of loader 'bootstrap')
at net.minecraft.launchwrapper.Launch.(Launch.java:34)
at net.minecraft.launchwrapper.Launch.main(Launch.java:28)
... 6 more
2024-01-12T17:57:58.310Z WARN mc-server-runner Minecraft server failed. Inspect logs above for errors that indicate cause. DO NOT report this line as an error. {"exitCode": 1}
2024-01-12T17:57:58.310Z INFO mc-server-runner Done
[init] Running as uid=1024 gid=100 with /data as 'drwxr-xr-x 6 1024 100 4096 Jan 12 17:39 /data'
[init] Resolving type given FORGE
[mc-image-helper] 17:58:02.043 INFO : Forge version 14.23.5.2859 for minecraft version 1.12.2 is already installed
[mc-image-helper] 17:58:05.119 INFO : Created/updated 1 property in /data/server.properties

[itzg]

Use a Java 8 tagged image

https://docker-minecraft-server.readthedocs.io/en/latest/versions/java/

Please read the documentation 😀

[DevDroid1]

i says that the java version is java 8 but I still get the same error should I use a specific version

[DevDroid1]

i need this server up urgently for a friend and the deadline is this evening (in the UK)

[itzg]

Oh...your comment changed 😀 and now I'm finding myself changing my comment. The logs are saying it is Java 8 but you're getting the exact same failure? Or is it something different? Please provide new logs.

I'll leave this for the old comment:

It'll be the image field -- you'll probably need to recreate the container since that is the first field it's probably asking for. Set it to itzg/minecraft-server:java8-multiarch

https://docs.portainer.io/user/docker/containers/add#image-configuration-section

[itzg]

For comparison, the key phrase in your original logs

Caused by: java.lang.ClassCastException: class jdk.internal.loader.ClassLoaders$AppClassLoader cannot be cast to class java.net.URLClassLoader 

[DevDroid1]

Thank you very much that has helped me out so much thank you for the quick reply and the advice