[GH-ISSUE #2464] Problems with setting up a modded Minecraft Server #1814

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opened 2026-02-27 02:59:11 +03:00 by kerem · 4 comments

kerem commented

2026-02-27 02:59:11 +03:00

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Originally created by @GameTime007 on GitHub (Aug 3, 2019).
Original GitHub issue: https://github.com/GameServerManagers/LinuxGSM/issues/2464

After much tinkering I could find the issue I'm having. Im not a total noob at this (have managed game servers for my friends for years -> Windows), but I'm totally out of ideas.

Im trying to set up a modded server based on the Resonant Rise Modpack. I installed a normal MCServer with LGSM and then replaced it's serverfiles with the RR Server files. After having done that and having pointed LGSM to the new filepath either the server starts with no issues, but completely without mods (eventhough I'm executing the forge-universal) (This happens when I replace the files wit a completely fresh set of RR Server). Or it spews out some weird Error codes (That happens when I already pre-ran the server on my normal PC):

A problem occurred running the Server launcher.java.lang.reflect.InvocationTarge
tException
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Nativ
e Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(Native
MethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(De
legatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:566)
at net.minecraftforge.fml.relauncher.ServerLaunchWrapper.run(ServerLaunc
hWrapper.java:70)
at net.minecraftforge.fml.relauncher.ServerLaunchWrapper.main(ServerLaun
chWrapper.java:34)
Caused by: java.lang.ClassCastException: class jdk.internal.loader.ClassLoaders$
AppClassLoader cannot be cast to class java.net.URLClassLoader (jdk.internal.loa
der.ClassLoaders$AppClassLoader and java.net.URLClassLoader are in module java.b
ase of loader 'bootstrap')
at net.minecraft.launchwrapper.Launch.(Launch.java:34)
at net.minecraft.launchwrapper.Launch.main(Launch.java:28)
... 6 more
[ OK ] Debug mcserver: Stopping debug

I know that this is some forge related issue, but the fix most poeple recommended (checking filenames) did not work. Is it even possible to launch the forge-universal.jar directly from Linux GSM? Or would it maybe be possible to call the provided "LaunchServer.sh" and start the server from there?

Any help and other tips would be greatly appreciated.

Originally created by @GameTime007 on GitHub (Aug 3, 2019). Original GitHub issue: https://github.com/GameServerManagers/LinuxGSM/issues/2464 After much tinkering I could find the issue I'm having. Im not a total noob at this (have managed game servers for my friends for years -> Windows), but I'm totally out of ideas. Im trying to set up a modded server based on the Resonant Rise Modpack. I installed a normal MCServer with LGSM and then replaced it's serverfiles with the RR Server files. After having done that and having pointed LGSM to the new filepath either the server starts with no issues, but completely without mods (eventhough I'm executing the forge-universal) (This happens when I replace the files wit a completely fresh set of RR Server). Or it spews out some weird Error codes (That happens when I already pre-ran the server on my normal PC): A problem occurred running the Server launcher.java.lang.reflect.InvocationTarge tException at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Nativ e Method) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(Native MethodAccessorImpl.java:62) at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(De legatingMethodAccessorImpl.java:43) at java.base/java.lang.reflect.Method.invoke(Method.java:566) at net.minecraftforge.fml.relauncher.ServerLaunchWrapper.run(ServerLaunc hWrapper.java:70) at net.minecraftforge.fml.relauncher.ServerLaunchWrapper.main(ServerLaun chWrapper.java:34) Caused by: java.lang.ClassCastException: class jdk.internal.loader.ClassLoaders$ AppClassLoader cannot be cast to class java.net.URLClassLoader (jdk.internal.loa der.ClassLoaders$AppClassLoader and java.net.URLClassLoader are in module java.b ase of loader 'bootstrap') at net.minecraft.launchwrapper.Launch.<init>(Launch.java:34) at net.minecraft.launchwrapper.Launch.main(Launch.java:28) ... 6 more [ OK ] Debug mcserver: Stopping debug I know that this is some forge related issue, but the fix most poeple recommended (checking filenames) did not work. Is it even possible to launch the forge-universal.jar directly from Linux GSM? Or would it maybe be possible to call the provided "LaunchServer.sh" and start the server from there? Any help and other tips would be greatly appreciated.

kerem

2026-02-27 02:59:11 +03:00

closed this issue
added the
game: Minecraft
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kerem commented

2026-02-27 02:59:12 +03:00

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@issue-label-bot[bot] commented on GitHub (Aug 3, 2019):

Issue-Label Bot is automatically applying the label type: bug to this issue, with a confidence of 0.63. Please mark this comment with 👍 or 👎 to give our bot feedback!

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@issue-label-bot[bot] commented on GitHub (Aug 3, 2019): Issue-Label Bot is automatically applying the label `type: bug` to this issue, with a confidence of 0.63. Please mark this comment with :thumbsup: or :thumbsdown: to give our bot feedback! Links: [app homepage](https://github.com/marketplace/issue-label-bot), [dashboard](https://mlbot.net/data/GameServerManagers/LinuxGSM) and [code](https://github.com/hamelsmu/MLapp) for this bot.

kerem commented

2026-02-27 02:59:12 +03:00

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Owner

@h3o66 commented on GitHub (Sep 13, 2020):

the default command can be overwritten with executable="./scriptname.sh" in the common or server config file in lgsm.

Sometimes it is also the case that only a old java version needs to be used, what can cause the server crashing when the version is to new of java.

If this answers you question, please close the issue

@h3o66 commented on GitHub (Sep 13, 2020): the default command can be overwritten with `executable="./scriptname.sh"` in the common or server config file in lgsm. Sometimes it is also the case that only a old java version needs to be used, what can cause the server crashing when the version is to new of java. If this answers you question, please close the issue

kerem commented

2026-02-27 02:59:12 +03:00

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Owner

@h3o66 commented on GitHub (Sep 19, 2020):

if you have further problems, please ask on discord for help

@h3o66 commented on GitHub (Sep 19, 2020): if you have further problems, please ask on discord for help

kerem commented

2026-02-27 02:59:12 +03:00

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@github-actions[bot] commented on GitHub (Sep 20, 2021):

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.

@github-actions[bot] commented on GitHub (Sep 20, 2021): This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.