1.16.5 failure to restart - Not a JSON Object

[Ash95]

Have a forge 1.16.5 server.  Will start and work as long as it is not restarted. Once restart is required server fails.

Debug text shows (after failure):

[01Jan2022 14:38:48.531] [main/FATAL] [net.minecraft.server.Main/]: Failed to start the minecraft server
java.lang.IllegalStateException: Not a JSON Object: null
    at com.google.gson.JsonElement.getAsJsonObject(JsonElement.java:90) ~[server-1.16.5-20210115.111550-extra.jar:?]
    at net.minecraft.util.registry.WorldSettingsImport$IResourceAccess$1.func_241879_a(WorldSettingsImport.java:193) ~[?:?]
    at net.minecraft.util.registry.WorldSettingsImport.func_241805_a_(WorldSettingsImport.java:131) ~[?:?]
    at net.minecraft.util.registry.WorldSettingsImport.func_240885_a_(WorldSettingsImport.java:105) ~[?:?]
    at com.mojang.serialization.DataResult.lambda$flatMap$10(DataResult.java:138) ~[?:?]
    at com.mojang.datafixers.util.Either$Left.map(Either.java:38) ~[?:?]
    at com.mojang.serialization.DataResult.flatMap(DataResult.java:136) ~[?:?]
    at net.minecraft.util.registry.WorldSettingsImport.func_241797_a_(WorldSettingsImport.java:104) ~[?:?]
    at net.minecraft.util.registry.SimpleRegistryCodec.func_240862_a_(SourceFile:35) ~[?:?]
    at com.mojang.serialization.DataResult.lambda$flatMap$10(DataResult.java:138) ~[?:?]
    at com.mojang.datafixers.util.Either$Left.map(Either.java:38) ~[?:?]
    at com.mojang.serialization.DataResult.flatMap(DataResult.java:136) ~[?:?]
    at net.minecraft.util.registry.SimpleRegistryCodec.decode(SourceFile:35) ~[?:?]
    at com.mojang.serialization.Decoder$2.decode(Decoder.java:63) ~[?:?]
    at com.mojang.serialization.Codec$2.decode(Codec.java:71) ~[?:?]
    at com.mojang.serialization.Decoder.parse(Decoder.java:18) ~[?:?]
    at com.mojang.serialization.codecs.FieldDecoder.decode(FieldDecoder.java:29) ~[?:?]
    at com.mojang.serialization.MapCodec$1.decode(MapCodec.java:34) ~[?:?]
    at com.mojang.serialization.codecs.RecordCodecBuilder$Instance$5.decode(RecordCodecBuilder.java:324) ~[?:?]
    at com.mojang.serialization.codecs.RecordCodecBuilder$2.decode(RecordCodecBuilder.java:107) ~[?:?]
    at com.mojang.serialization.MapDecoder.lambda$compressedDecode$0(MapDecoder.java:52) ~[?:?]
    at com.mojang.serialization.DataResult.lambda$flatMap$10(DataResult.java:138) ~[?:?]
    at com.mojang.datafixers.util.Either$Left.map(Either.java:38) ~[?:?]
    at com.mojang.serialization.DataResult.flatMap(DataResult.java:136) ~[?:?]
    at com.mojang.serialization.MapDecoder.compressedDecode(MapDecoder.java:52) ~[?:?]
    at com.mojang.serialization.MapCodec$MapCodecCodec.decode(MapCodec.java:91) ~[?:?]
    at com.mojang.serialization.Decoder$1.decode(Decoder.java:49) ~[?:?]
    at com.mojang.serialization.Codec$2.decode(Codec.java:71) ~[?:?]
    at com.mojang.serialization.Decoder.parse(Decoder.java:18) ~[?:?]
    at net.minecraft.server.Main.lambda$main$0(Main.java:153) ~[?:?]
    at com.mojang.serialization.DataResult.lambda$flatMap$10(DataResult.java:138) ~[?:?]
    at com.mojang.datafixers.util.Either$Left.map(Either.java:38) ~[?:?]
    at com.mojang.serialization.DataResult.flatMap(DataResult.java:136) ~[?:?]
    at net.minecraft.server.Main.main(Main.java:153) ~[?:?]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_311]
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_311]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_311]
    at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_311]
    at net.minecraftforge.fml.loading.FMLServerLaunchProvider.lambda$launchService$0(FMLServerLaunchProvider.java:51) ~[forge-1.16.5-36.2.22.jar:36.2]
    at cpw.mods.modlauncher.LaunchServiceHandlerDecorator.launch(LaunchServiceHandlerDecorator.java:37) [modlauncher-8.0.9.jar:?]
    at cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:54) [modlauncher-8.0.9.jar:?]
    at cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:72) [modlauncher-8.0.9.jar:?]
    at cpw.mods.modlauncher.Launcher.run(Launcher.java:82) [modlauncher-8.0.9.jar:?]
    at cpw.mods.modlauncher.Launcher.main(Launcher.java:66) [modlauncher-8.0.9.jar:?]
    at net.minecraftforge.server.ServerMain$Runner.runLauncher(ServerMain.java:63) [forge-1.16.5-36.2.22.jar:?]
    at net.minecraftforge.server.ServerMain$Runner.access$100(ServerMain.java:60) [forge-1.16.5-36.2.22.jar:?]
    at net.minecraftforge.server.ServerMain.main(ServerMain.java:57) [forge-1.16.5-36.2.22.jar:?]
 

Full debug file at:

https://gist.github.com/pjmagg/f95dabbea428c9c92eb87ab5d75bfd59

Don't have a clue as to what I'm looking at, so any help greatly appreciated.

[Ash95]

Starting the server - taking it from a just installed program adding mods and then starting the server (running the jar file) thus allowing others to play.

Restarting the server - taking the server offline, shutting it down, adding mods then reloading (restarting) the server putting it back online for players to access.

Edited January 4, 2022 by Ash95
clairity

[Ash95]

no same world. never gets far enough in the startup process to make changes the additional mods would cause. Also, when I just shutdown the server and restart it without making any changes to the software package.  

[Ash95]

to me starting a server is when you first turn it on for playing. Like installing the software package and running the server jar thus allowing players to access the game.  Restarting is having stopped the server software, ie exiting the server jar program, then re-executing the server jar software so players can once again access the game.  

The forge/minecraft server software package resides on a hardware server which remains on 24/7 except for maintenance or power interruptions.

[Ash95]

It is all software based. To me a restart means the server program is in the same condition as when it was shutdown.  The folders and the data contained in them such as "world" has not changed, players retain their inventory continuing the game from where they left off. This is usually caused by power interruption or desire to add/subtract mods. Fresh start is a new game with a new world folder, new config folder, new journeymap folder and players start with a default inventory.

[Ash95]

don't think that i denied the world is corrupted but what i can't figure out is why. if i start a server package with no mods, shut it down and then restart everything works. If i add mods start the server everything is fine. Shut it down and then restart i get the above error. Not sure which mod (if it is a mod) is causing the corruption since i change which mods i use in testing to see if i can pin the corruption to a specific mod. With 120 mods it takes a while to "brute force"  plus it seems that it really doesn't matter which mods i'm using. 

[Ash95]

It is something triggered by the processing of level.dat file but i am unable to determine what