[Unsolved] Interpreting stacktrace/error logs/crash logs - help!

Hello Bukkit forums,

My server has been plagued with issue after issue, crash after crash this month, and it's getting more unbearable everyday. I look through the stacktraces for the errors and I can never pinpoint the exact cause. This is making me want to pull my hair out because it's taking up far more of my time than it should be. I have my three latest stacktraces pasted below. Thank you for your help!

Stacktrace #1
Stacktrace #2
Stacktrace #3

Thanks in advance!

- jflory7

 

jflory7
So it appears that you're running Garry's Mod?

 

martian3333 Errr– I myself am not. The Minecraft host I use does sell Garry's Mod servers, though, and it could be that there are some running on the same node as our server.

What part of the crash look made it look like we were running Garry's Mod?

 

jflory7
I think i researched something I saw and got a bad answer. Sorry about that.... so unfortunately I can't find anything in the stack trace that tells me anything. Hopefully someone else can find it. I just saw another post with what looks like the exact same issue, but with no answers.

 

martian3333 Well, thanks for trying to help.

If anyone else out there has any ideas, just let me know! I'm willing to try /almost/ anything.

 

The error is caused by a method which changes a collection while iterating over the collection.
However, the stacktrace points to Mojang Code to a line, which should not throw such a exception.

Do you have any mods on your server?

 

Syd That's definitely odd… and yes, we have some plugins on our server. The plugins we have are as follows:

• GroupManager v2.0 (Pre2.12.1.2)
• Jets v1.05
• WorldEdit
• NoCheatPlus v3.10.2-SNAPSHOT
• PlayerLink v1.3 [jflory7]
• AdminPrivateChat v2.0
• Vault v1.2.24-b304
• ScheduledAnnouncer2 v2.7
• Multiverse-Core v2.5-b670
• Votifier v1.9
• WorldGuard v5.8
• Essentials vPre2.12.1.2
• EssentialsSpawn vPre2.12.1.2
• Multiverse-Portals v2.5-b696
• Enjin Minecraft Plugin v2.4.9
• EssentialsChat vPre2.12.1.2

This is everything.

 

jflory7
I actually meant mods, not plugins.
Plugins should not interfere NMS Code, but mods do.

(But I guess you don't have any mods)

So, can you reproduce the crash? Have you tried reproducing it without any plugins?
It could be a plugin, which tries to change to access the BukkitAPI in a async thread.

 

Syd Oh, yeah, it wouldn't be a mod. Our server does not run any client modifications.

I'm positive it has to be a plugin causing it, but I'm not in a position where I could remove all of our plugins at once to test for this. My server has a full time dependency on some of these plugins (i.e. WorldGuard, GroupManager, etc.) so removing them even temporarily is not an option. Does the crash log point towards anything that could even be remotely an issue?

 

jflory7
Nope, it doesn't give a hint, what exactly causes the error.
I've look through all plugins that are unknown to me, if they contain a async thread, but I found nothing.

I think your only option is to test our every plugin (make backups or try it in a test enviroment), or to find out how to reproduce the error.

 

Syd
Which plugins do have Async threads of the list that I posted (just so I have an idea of where to start)?

 

jflory7
I don't know, but actually I occured the same crash on my server yesterday, too.

The only matching plugins are WorldEdit, WorldGuard, Essentials + Spawn (but the 2.11.1)
And I doubt that these plugin have such a severe error.

Actually I start to belive it's either a MC Bug or a CraftBukkit Bug...

 

Syd I've just updated to the latest developmental build of Bukkit, so I will see if that fixes anything.