Valheim server goes offline randomly

[rytissav]

Hello,
lately my LinuxGSM Valheim server goes offline at random times when there is no people online.

I can find logged this:

(Filename: ./Runtime/Export/Debug/Debug.bindings.h Line: 39)

05/25/2021 10:46:56: Saved 713474 zdos

(Filename: ./Runtime/Export/Debug/Debug.bindings.h Line: 39)

05/25/2021 10:46:56: World saved ( 2787.941ms )

(Filename: ./Runtime/Export/Debug/Debug.bindings.h Line: 39)

05/25/2021 10:56:38:  Connections 0 ZDOS:713474  sent:0 recv:0

(Filename: ./Runtime/Export/Debug/Debug.bindings.h Line: 39)

Unloading 0 Unused Serialized files (Serialized files now loaded: 0)

Unloading 0 unused Assets to reduce memory usage. Loaded Objects now: 1116271.
Total: 1237.691573 ms (FindLiveObjects: 110.150168 ms CreateObjectMapping: 46.873782 ms MarkObjects: 1078.770305 ms  DeleteObjects: 1.891366 ms)

05/25/2021 11:06:39:  Connections 0 ZDOS:713474  sent:0 recv:0

(Filename: ./Runtime/Export/Debug/Debug.bindings.h Line: 39)

Unloading 0 Unused Serialized files (Serialized files now loaded: 0)

Unloading 0 unused Assets to reduce memory usage. Loaded Objects now: 1116271.
Total: 1100.920312 ms (FindLiveObjects: 105.537817 ms CreateObjectMapping: 31.798343 ms MarkObjects: 962.213927 ms  DeleteObjects: 1.364957 ms)

05/25/2021 11:06:56: clone 1590

(Filename: ./Runtime/Export/Debug/Debug.bindings.h Line: 39)

05/25/2021 11:07:01: Saved 713474 zdos

(Filename: ./Runtime/Export/Debug/Debug.bindings.h Line: 39)

exception.c:79: Could not allocate 136 bytes assembly:<unknown assembly> type:<unknown type> member:(null) signature:<none>

Caught fatal signal - signo:6 code:-6 errno:0 addr:0x3ea00001f38
Obtained 22 stack frames.
#0  0x007fc071428730 in (Unknown)
#1  0x007fc07128c7bb in (Unknown)
#2  0x007fc071277535 in (Unknown)
#3  0x007fc070cdf8a4 in (Unknown)
#4  0x007fc070cefc50 in (Unknown)
#5  0x007fc070cefce3 in (Unknown)
#6  0x007fc070ce3b75 in (Unknown)
#7  0x007fc070c48720 in (Unknown)
#8  0x007fc070ce4f62 in (Unknown)
#9  0x007fc070ce5117 in (Unknown)
#10 0x007fc070c498bc in (Unknown)
#11 0x007fc070c8d1cd in (Unknown)
#12 0x0000004054deaf in (wrapper managed-to-native) object:__icall_wrapper_ves_icall_array_new_specific (intptr,int)
#13 0x0000004068f62c in ZNet:SaveWorldThread ()
#14 0x000000405f1254 in System.Threading.ExecutionContext:Run (System.Threading.ExecutionContext,System.Threading.ContextCallback,object,bool)
#15 0x007fc070b1b7c5 in (Unknown)
#16 0x007fc070c8b37c in (Unknown)
#17 0x007fc070ca56b4 in (Unknown)
#18 0x007fc070d0700f in (Unknown)
#19 0x007fc070cfbd7a in (Unknown)
#20 0x007fc07141dfa3 in (Unknown)
#21 0x007fc07134e4cf in (Unknown)

OS:
Distributor ID: Debian
Description: Debian GNU/Linux 10 (buster)
64bit

How can I fix this?

[visdmin]

Hello,

To be honest i don't know what could cause this, it could be issue with the valheim server version (bug) or library in your system that causes this, very hard to tell.

---

But I may have temporary solution for you until some one can find out reason for the actual problem:

We can use cron job to check the server status periodically and use this information to restart the server if the server has become unresponsive.

I made script that uses ./vhserver monitor command to resolve if server is responsive:

• If the check fails the script tries to restart the server.
• if the check is OK no more actions are done.
• script logs status information to file, so you can check if the server has been restarted.

Script has 2 variables:

• VH_SERVER_PATH that has to set to point to your vhserver bash executable.
• LOG_FILE_PATH where you can set path to log file (script writes status info to this file)

---

Example:
All the following is done with the user that is used to run the valheim server.
I have my valheim server installed in the following directory: /home/lgsm-daemon/

1. I imported my checker script to file
   • /home/lgsm-daemon/vhserver-cron-checker.sh
2. I used vim to edited the script and set my VH_SERVER_PATH and LOG_FILE_PATH variables.
   • VH_SERVER_PATH="/home/lgsm-daemon/vhserver"
   • LOG_FILE_PATH="/home/lgsm-daemon/vhserver-availability-check.log"
3. Made the script executable

   chmod +x /home/lgsm-daemon/vhserver-cron-checker.sh

4. Running the script manually when server was running created the log file with the following content:

   /home/lgsm-daemon/vhserver-cron-checker.sh

   cat /home/lgsm-daemon/vhserver-availability-check.log

   2021-08-31 16:05:01 +0200 :: [ INFO ]: Starting server status check (server: /home/lgsm-daemon/vhserver)
   2021-08-31 16:05:05 +0200 :: [ INFO ]: Executing server command (cmd: '/home/lgsm-daemon/vhserver monitor')
   [  OK  ] Monitoring vhserver: Checking session: OK
   [  OK  ] Monitoring vhserver: Querying port: gsquery: 0.0.0.0:2457 : 0/1: DELAY
   2021-08-31 16:05:05 +0200 :: [ INFO ]: Server status check succesful (server: /home/lgsm-daemon/vhserver)
   

5. Running the script manually when server was not running created the log file with the following content:

   /home/lgsm-daemon/vhserver-cron-checker.sh

   cat /home/lgsm-daemon/vhserver-availability-check.log

   2021-08-31 16:23:01 +0200 :: [ INFO ]: Starting server status check (server: /home/lgsm-daemon/vhserver)
   2021-08-31 16:23:03 +0200 :: [ INFO ]: Executing server command (cmd: '/home/lgsm-daemon/vhserver monitor')
   [ ERROR ] Monitoring vhserver: Checking lockfile: No lockfile found: ERROR
   * Start vhserver to run monitor.
   2021-08-31 16:23:03 +0200 :: [ WARN ]: Server status check failed (server: /home/lgsm-daemon/vhserver)
   2021-08-31 16:23:03 +0200 :: [ INFO ]: Restarting vhserver (server: /home/lgsm-daemon/vhserver)
   2021-08-31 16:23:09 +0200 :: [ INFO ]: Executing server command (cmd: '/home/lgsm-daemon/vhserver restart')
   [ INFO ] Stopping vhserver: visdmin vh server is already stopped
   [  OK  ] Starting vhserver: visdmin vh server
   2021-08-31 16:23:09 +0200 :: [ INFO ]: vhserver restarted succesfully (server: /home/lgsm-daemon/vhserver, status: OK)
   2021-08-31 16:23:09 +0200 :: [ INFO ]: Sleeping for 10 seconds, to recheck the server status (server: /home/lgsm-daemon/vhserver)
   2021-08-31 16:23:24 +0200 :: [ INFO ]: Executing server command (cmd: '/home/lgsm-daemon/vhserver monitor')
   [  OK  ] Monitoring vhserver: Checking session: OK
   [  OK  ] Monitoring vhserver: Querying port: gsquery: 0.0.0.0:2457 : 0/1: DELAY
   2021-08-31 16:23:24 +0200 :: [ INFO ]: Server restarted successfully (server: /home/lgsm-daemon/vhserver)
   

6. Finally i made cron jon that runs the script every minute:

   crontab -e

   • Input the following and save:

   * * * * * /home/lgsm-daemon/vhserver-cron-checker.sh
   

IMPORTANT:
Please note that setting up the cron job will try to restart your valheim server every minute even if you manually stop it.
So if you wish to stop your server and make it to not automatically restart you have to remove the cron job:

crontab -e

• Remove the following line and save:

* * * * * /home/lgsm-daemon/vhserver-cron-checker.sh

For more information about crontab / cron jobs check lgsm documentation:
https://docs.linuxgsm.com/configuration/cronjobs#crontab

---

The checker script:
vhserver-cron-checker.sh: https://gist.github.com/visdmin/ae74a2d1ca0ffef7ab4fd8bc17deabfd