I am stuck.... I have zero mods in the folder, just trying to get Forge to run... if I run the normal Minecraft server, it works fine... vanilla. As soon as I launch the Forge server, I get the following:
root@minecraft:/home/minecraft# java -Xms2G -Xmx5G -jar forge-1.14.4-28.2.23.jar --nogui
[22:14:13] [main/INFO] [cp.mo.mo.Launcher/MODLAUNCHER]: ModLauncher running: args [--gameDir, ., --launchTarget, fmlserver, --fml.forgeVersion, 28.2.23, --fml.mcpVersion, 20190829.143755, --fml.mcVersion, 1.14.4, --fml.forgeGroup, net.minecraftforge, --nogui]
[22:14:13] [main/INFO] [cp.mo.mo.Launcher/MODLAUNCHER]: ModLauncher 4.1.0+62+5bfa59b starting: java version 11.0.8 by Debian
[22:14:13] [main/INFO] [ne.mi.fm.lo.FixSSL/CORE]: Added Lets Encrypt root certificates as additional trust
[22:14:14] [main/INFO] [STDERR/]: [jdk.nashorn.api.scripting.NashornScriptEngine:<init>:143]: Warning: Nashorn engine is planned to be removed from a future JDK release
[22:14:15] [main/INFO] [cp.mo.mo.LaunchServiceHandler/MODLAUNCHER]: Launching target 'fmlserver' with arguments [--gameDir, ., --nogui]
Exception in thread "main" [22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1050]: java.lang.RuntimeException: java.lang.UnsupportedOperationException
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1050]: at cpw.mods.modlauncher.LaunchServiceHandlerDecorator.launch(LaunchServiceHandlerDecorator.java:39)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1050]: at cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:54)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1050]: at cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:72)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1050]: at cpw.mods.modlauncher.Launcher.run(Launcher.java:81)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1050]: at cpw.mods.modlauncher.Launcher.main(Launcher.java:65)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1050]: at net.minecraftforge.server.ServerMain$Runner.runLauncher(ServerMain.java:63)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1050]: at net.minecraftforge.server.ServerMain$Runner.access$100(ServerMain.java:60)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1050]: at net.minecraftforge.server.ServerMain.main(ServerMain.java:57)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: Caused by: java.lang.UnsupportedOperationException
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at org.objectweb.asm.ClassVisitor.visitNestMemberExperimental(ClassVisitor.java:248)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at org.objectweb.asm.ClassReader.accept(ClassReader.java:651)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at org.objectweb.asm.ClassReader.accept(ClassReader.java:391)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at cpw.mods.modlauncher.TransformerClassWriter.computeHierarchy(TransformerClassWriter.java:83)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at cpw.mods.modlauncher.TransformerClassWriter.access$100(TransformerClassWriter.java:35)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at cpw.mods.modlauncher.TransformerClassWriter$SuperCollectingVisitor.visit(TransformerClassWriter.java:129)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at org.objectweb.asm.ClassReader.accept(ClassReader.java:525)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at org.objectweb.asm.ClassReader.accept(ClassReader.java:391)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at cpw.mods.modlauncher.TransformerClassWriter.computeHierarchy(TransformerClassWriter.java:83)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at cpw.mods.modlauncher.TransformerClassWriter.access$100(TransformerClassWriter.java:35)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at cpw.mods.modlauncher.TransformerClassWriter$SuperCollectingVisitor.visit(TransformerClassWriter.java:129)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at org.objectweb.asm.ClassReader.accept(ClassReader.java:525)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at org.objectweb.asm.ClassReader.accept(ClassReader.java:391)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at cpw.mods.modlauncher.TransformerClassWriter.computeHierarchy(TransformerClassWriter.java:83)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at cpw.mods.modlauncher.TransformerClassWriter.access$100(TransformerClassWriter.java:35)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at cpw.mods.modlauncher.TransformerClassWriter$SuperCollectingVisitor.visit(TransformerClassWriter.java:129)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at org.objectweb.asm.ClassReader.accept(ClassReader.java:525)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at org.objectweb.asm.ClassReader.accept(ClassReader.java:391)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at cpw.mods.modlauncher.TransformerClassWriter.computeHierarchy(TransformerClassWriter.java:83)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at cpw.mods.modlauncher.TransformerClassWriter.getSupers(TransformerClassWriter.java:54)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at cpw.mods.modlauncher.TransformerClassWriter.getCommonSuperClass(TransformerClassWriter.java:99)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at org.objectweb.asm.SymbolTable.addMergedType(SymbolTable.java:1209)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at org.objectweb.asm.Frame.merge(Frame.java:1293)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at org.objectweb.asm.Frame.merge(Frame.java:1175)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at org.objectweb.asm.MethodWriter.computeAllFrames(MethodWriter.java:1604)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at org.objectweb.asm.MethodWriter.visitMaxs(MethodWriter.java:1540)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at org.objectweb.asm.tree.MethodNode.accept(MethodNode.java:807)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at org.objectweb.asm.tree.MethodNode.accept(MethodNode.java:687)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at org.objectweb.asm.tree.ClassNode.accept(ClassNode.java:436)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at cpw.mods.modlauncher.ClassTransformer.transform(ClassTransformer.java:121)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at cpw.mods.modlauncher.TransformingClassLoader$DelegatedClassLoader.findClass(TransformingClassLoader.java:241)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at cpw.mods.modlauncher.TransformingClassLoader.loadClass(TransformingClassLoader.java:128)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at cpw.mods.modlauncher.TransformingClassLoader.loadClass(TransformingClassLoader.java:98)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at java.base/java.lang.Class.forName0(Native Method)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at java.base/java.lang.Class.forName(Class.java:398)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at net.minecraftforge.fml.loading.FMLServerLaunchProvider.lambda$launchService$0(FMLServerLaunchProvider.java:51)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: at cpw.mods.modlauncher.LaunchServiceHandlerDecorator.launch(LaunchServiceHandlerDecorator.java:37)
[22:14:16] [main/INFO] [STDERR/]: [java.lang.ThreadGroup:uncaughtException:1059]: ... 7 more