Hey everyone, I need some help finding out why my server keeps crashing.  Looks like its going down once per day.  Here is whats at the tail end of my logfile:

Thread 3 (Thread 0x7f9cee14f700 (LWP 3272669)):
#0 syscall () at ../sysdeps/unix/sysv/linux/x86_64/syscall.S:38
#1 0x00007f9da35e819a in CappedSemaphor*:*:*:*:*:*:*:*WaitForSignalImpl() () from /home/rustserver/serverfiles/UnityPlayer.so
#2 0x00007f9da3691ebe in JobQueu*:*:*:*:*:*:*:*ProcessJobs(JobQueu*:*:*:*:*:*:*:*ThreadInfo*, void*) () from /home/rustserver/serverfiles/UnityPlayer.so
#3 0x00007f9da3691360 in JobQueu*:*:*:*:*:*:*:*WorkLoop(void*) () from /home/rustserver/serverfiles/UnityPlayer.so
#4 0x00007f9da376a33a in Thr*:*:*:*:*:*:*:*RunThreadWrapper(void*) () from /home/rustserver/serverfiles/UnityPlayer.so
#5 0x00007f9da2c4a609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#6 0x00007f9da2b6f163 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 2 (Thread 0x7f9da1d35700 (LWP 3272668)):
#0 futex_abstimed_wait_cancelable (private=0, abstime=0x0, clockid=0, expected=0, futex_word=0x7f9da2821770) at ../sysdeps/nptl/futex-internal.h:320
#1 do_futex_wait (sem=sem@entry=0x7f9da2821770, abstime=0x0, clockid=0) at sem_waitcommon.c:112
#2 0x00007f9da2c544e8 in __new_sem_wait_slow (sem=0x7f9da2821770, abstime=0x0, clockid=0) at sem_waitcommon.c:184
#3 0x00007f9da24cd7a4 in ?? () from /home/rustserver/serverfiles/RustDedicated_Data/MonoBleedingEdge/x86_64/libmonobdwgc-2.0.so
#4 0x00007f9da24cd9d3 in ?? () from /home/rustserver/serverfiles/RustDedicated_Data/MonoBleedingEdge/x86_64/libmonobdwgc-2.0.so
#5 0x00007f9da24cdb28 in ?? () from /home/rustserver/serverfiles/RustDedicated_Data/MonoBleedingEdge/x86_64/libmonobdwgc-2.0.so
#6 0x00007f9da249f18c in ?? () from /home/rustserver/serverfiles/RustDedicated_Data/MonoBleedingEdge/x86_64/libmonobdwgc-2.0.so
#7 0x00007f9da25009cf in GC_inner_start_routine () from /home/rustserver/serverfiles/RustDedicated_Data/MonoBleedingEdge/x86_64/libmonobdwgc-2.0.so
#8 0x00007f9da24f573a in GC_call_with_stack_base () from /home/rustserver/serverfiles/RustDedicated_Data/MonoBleedingEdge/x86_64/libmonobdwgc-2.0.so
#9 0x00007f9da2c4a609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#10 0x00007f9da2b6f163 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 1 (Thread 0x7f9da2a3b740 (LWP 3272662)):
#0 0x00007f9da2b2d26f in __GI___clock_nanosleep (clock_id=clock_id@entry=0, flags=flags@entry=0, req=0x7fffef4bb3c8, rem=0x0) at ../sysdeps/unix/sysv/linux/clock_nanosleep.c:78
#1 0x00007f9da2b32ef7 in __GI___nanosleep (requested_time=<optimized out>, remaining=<optimized out>) at nanosleep.c:27
#2 0x00007f9da376a541 in ThreadHelper::SleepInSeconds(double) () from /home/rustserver/serverfiles/UnityPlayer.so
#3 0x00007f9da3682efe in TimeManager::EndSyncFrame(TimeManager::SyncBehaviour) () from /home/rustserver/serverfiles/UnityPlayer.so
#4 0x00007f9da3682fc6 in TimeManager::Sync(TimeManager::SyncPosition) () from /home/rustserver/serverfiles/UnityPlayer.so
#5 0x00007f9da36e3551 in InitPlayerLoopCallbacks()::InitializationPlayerUpdateTimeRegistrator::Forward() () from /home/rustserver/serverfiles/UnityPlayer.so
#6 0x00007f9da36dd85e in ExecutePlayerLoop(NativePlayerLoopSystem*) () from /home/rustserver/serverfiles/UnityPlayer.so
#7 0x00007f9da36dd8a1 in ExecutePlayerLoop(NativePlayerLoopSystem*) () from /home/rustserver/serverfiles/UnityPlayer.so
#8 0x00007f9da36dddda in PlayerLoop() () from /home/rustserver/serverfiles/UnityPlayer.so
#9 0x00007f9da38476de in PlayerMain(int, char**) () from /home/rustserver/serverfiles/UnityPlayer.so
#10 0x00007f9da2a740b3 in __libc_start_main (main=0x55e1a7200780 <main>, argc=39, argv=0x7fffef4bbe28, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffef4bbe18) at ../csu/libc-start.c:308
#11 0x000055e1a7200699 in _start ()
[Inferior 1 (process 3272662) detached]

=================================================================
Got a SIGSEGV while executing native code. This usually indicates
a fatal error in the mono runtime or one of the native libraries
used by your application.
=================================================================

Caught fatal signal - signo:11 code:1 errno:0 addr:(nil)
Obtained 8 stack frames.
#0 0x007f9da2c563c0 in funlockfile
#1 0x007f9da106f2f0 in Java_com_easyanticheat_server_GameServerJNI_CreateGameServer
#2 0x007f9da106d6ad in Java_com_easyanticheat_server_GameServerJNI_CreateGameServer
#3 0x007f9da106aeb4 in Java_com_easyanticheat_server_GameServerJNI_CreateGameServer
#4 0x007f9da106eb80 in Java_com_easyanticheat_server_GameServerJNI_CreateGameServer
#5 0x007f9da106f3ff in Java_com_easyanticheat_server_GameServerJNI_CreateGameServer
#6 0x007f9da2c4a609 in start_thread
#7 0x007f9da2b6f163 in clone
Aborted (core dumped)

Is there anything I can do to resolve or troubleshoot this issue?  Looks like its out of my control but I'd like opinions from the more experiened.  Thanks everyone!

Luckly you are on linux so this is a doddle...

spin off an IDENTICAL bit image of the server, with no users and unloaded plugins.
see if it crashes the same, if not add the plugins back in. and fault find.

Also is your server fully uptodate for linux... they recently did a java update...

I can't seem to be able to run two instances of rust server on my machine & network - I've tried before in the past with no success.  Ive updates linux packages and it still crashes, I'm trying to find a time to bring the machine down for a reboot still.  In the meantime, I've posted the entire crash report here:
https://pastebin.com/CA3FLLZf
Maybe there are more clues in there?

So is THIS issue related to you FIRST issue?

Yes, it was all the same issue.
I did a ./rustserver validate and it found some cinvalid files and fixedthem.  I also needed to update oxide mod itself.  The issue has been resolved and was user errors.