I have a Minecraft Server running on Linux.
I use to start the server, a start.sh file with following content:
(This content starts a screen session and the minecraft server)
screen -S {ScreenSession} java -Xmx2G -Xms2G -jar spigot-1.18.1.jar
If I use /restart ingame, the screen session will end and the server won't start. So I have to go into the Linux Server and start the Minecraft Server again.
My question:
How can I make it so, if I use /restart that the server will restart with a active screen session.
If have tried many things.
I hope someone can help me,
~Kitty Cat Craft
There is multiple way to achieve what you want.
If you have lot of servers, you can use a quick bash script with an auto restart like that:
#!/bin/sh
while true
do
java -Xmx2G -Xms2G -jar spigot-1.18.1.jar --nogui
sleep 5
done
When you will stop, it will wait 5 seconds then restart.
With this, you can use: screen -dmS <screenName> sh myScript.sh which will run the script into another screen. It's usefull when you run it from a script which run lot of server, like that:
screen -dmS srv1 sh srv1.sh
screen -dmS srv2 sh srv2.sh
screen -dmS srv3 sh srv3.sh
You can also, if you have only one server, just firstly use screen -S screenName. Then, when you are in the screen, run the script that restart automatically (the script that I gave at first).
Also, prefer use /stop than /restart, because spigot will try to find the script. And if it success, it will run a second time the same script, and so will have ghost process.
Related
I have a discord bot running on a raspberry pi that i need to restart every day, I'm trying to do this through crontab but with no luck.
It manages to kill the active screen processes but never starts an instance, not that I can see with "screen -ls" and I can tell that it doesn't create one that I can't see as the bot itself does not come online.
Here is the script:
#!/bin/bash
sudo pkill screen
sleep 2
screen -dmS discordBot
sleep 2
screen -S "discordBot" -X stuff "node discordBot/NEWNEWNEWN\n"
Here is also the crontab:
0 0 * * * /bin/bash /home/admin/discordBot/script.sh
Is it possible to have crontab run a screen session? And if so how?
Previously I tried putting the screen command stright into cron but now I have it in a bash script instead.
If I run the script in the terminal it works perfectly, it’s just cron where it fails. Also replacing "screen" with the full path "/usr/bin/screen" does not change anything.
So the best way of doing it, without investigating the underlying problem would be to create a systemd service and putting a restart command into cron.
/etc/systemd/system/mydiscordbot.service:
[Unit]
Description=A very simple discord bot
[Service]
Type=simple
ExecStart=node /path/to/my/discordBot.js
[Install]
WantedBy=multi-user.target
Now you can run your bot with systemctl start mydiscordbot and can view your logs with journalctl --follow -u mydiscord bot
Now you only need to put
45 2 * * * systemctl restart discordbot
into root's crontab and you should be good to go.
You probably should also write the logs into a logfile, maybe /var/log/mydiscordbot.log, but how and if you do that is up to you.
OLD/WRONG ANSWER:
cron is run with a minimal environment, and depending on your os, /usr/bin/ is probably not in the $PATH var. screen is mostlikely located at /usr/bin/screen, so cron can't run it because it can't find the screen binary. try replacing screen in your script with /usr/bin/screen
But the other question here is: Why does your discord bot need to be restarted every day. I run multiple bots with 100k+ users, and they don't need to be restarted at all. Maybe you should open a new question with the error and some code snippets.
I don't know what os your rpi is running, but I had a similar issue earlier today trying to get vms on a server to launch a terminal and run a python script with crontab. I found a very easily solution to automatically restart it on crashes, and to run something simply in the background. Don't rely on crontab or an init service. If your rpi as an x server running, or anything that can be launched on session start, there is a simple shell solution. Make a bash script like
while :; do
/my/script/to/keep/running/here -foo -bar -baz >> /var/log/myscriptlog 2>&1
done
and then you would start it on .xprofile or some similar startup operation like
/path/to/launcher.sh &
to have it run the background. It will restart automatically everytime it closes if started in something like .xprofile, .xinitrc, or anything ran at startup.
Then maybe make a cronjob to restart the raspberry pi or whatever system is running the script but this script wil restart the service whenever it's closed anyway. Maybe you can put that cronjob on a script but I don't think it would launch the GUI.
Some other things you can do to launch a GUI terminal in my research with cronjob that you can try, though they didn't work for my situation on these custom linux vms, and that I read was a security risk to do this from a cronjob, is you can specify the display.
* * * * * DISPLAY=:0 /your/gui/stuff/here
but you would would need to make sure the user has the right permissions and it's considered an unsafe hack to even do this as far as I have read.
for my issue, I had to launch a terminal that stayed open, and then changed to the directory of a python script and ran the script, so that the local files in directory would be called in the python script. here is a rough example of the "launcher.sh" I called from the startup method this strange linux distro used lol.
#!/bin/sh
while :; do
/usr/bin/urxvt -e /bin/bash -c "cd /path/to/project && python loader.py"
done
Also check this source for process management
https://mywiki.wooledge.org/ProcessManagement
I am trying to run a minecraft server on a remote linux instance.
I would like the instance to start up the server on a screen named serverscreen which is owned by the user named minecraft once the system boots up, and run a stop command to the serverscreen when the instance shuts down. Then, it needs to wait untill the server has stopped before actually shutting down.
I am quite new to linux but I have managed to come up with a few commands that work, but I have issues trying to start and stop the server automatically.
I have tried quite a few things, like creating a .sh script to run on startup with crontab -e #reboot script.sh, or create a file in etc/rc.local with #!/bin/sh sh script.sh, but those methods didn't seem to work properly for me. Also, they do not run un shutdown unfortunately. Therefore, I thought it would be best to create a service file named minecraft.service with the following commands:
[Unit]
Description=Minecraft Server
After=network.target
[Service]
User=minecraft
Nice=5
KillMode=none
SuccessExitStatus=0 1
InaccessibleDirectories=/root /sys /srv /media -/lost+found
NoNewPrivileges=true
WorkingDirectory=/opt/minecraft/server
ReadWriteDirectories=/opt/minecraft/server
#### Command to start the server.
ExecStart=sudo -u minecraft screen -dmS serverscreen java -Xms6G -Xmx6G -jar /opt/minecraft/server/forgeserver.jar nogui
#### Command to stop the server.
ExecStop=sudo -u minecraft screen -S serverscreen -p 0 -X eval "stuff stop^M"
##### Try to wait untill the server has stopped. I am not sure about this line of code since I haven't been able to test it properly.
ExecStop=/bin/bash -c "while ps -p $MAINPID > /dev/null; do /bin/sleep 1; done"
[Install]
WantedBy=multi-user.target
but when running this, it gives me an error saying that I did not provide an absolute path for something.
Could someone help me setup a service file that will boot up the server on a screen named serverscreen for the user minecraft, and run command stop when the instance shuts down after the server has been stopped?
Thanks to #Riz, the service now works as intended by using a bash script in order to run the commands.
I have a java program that starts a TCP/IP game server.
I have an angular application that speaks with an express node.js server to start/stop the game server.
When the button start is clicked the following operation is performed in the nodejs server:
shell.exec('/web/starter.sh');
And this is my script:
:set fileformat=unix
#!/bin/sh
screen -RD server -X quit;
screen -dmS server;
cd ~/cadesim-monomer;
java -jar CadeServerEngine.jar;
It works, it starts the server. But whenever I click start again, it doesn't restart the server as it should. It should kill the screen and restart?
What did I do wrong?
The issue is that the server commands aren't running inside the detached screen session. They are running after both of the screen commands.
To run a command in detached screen session for this example would need to use:
screen -dmS server sh -c "cd ~/cadesim-monomer; java -jar CadeServerEngine.jar"
Or you can put the server and its setup in its own shell file and that file would have a similar appearance to a daemontools run script. And then you would have a command like:
screen -dmS server ./server.sh
Also the shebang line should be the first line in the file. The script just happens to work because the shell is the default interpreter. It produces the error line 1: :set: command not found. The VIM mode setting should occur in a comment on the second line.
I am trying to make a minecraft server for a while and I have a little problem with a stop script. My startup script ( i want to mention in , just in case of something ) looks like this:
#!/bin/sh
screen -S server java -Xms2G -Xmx2G -XX:+UseConcMarkSweepGC -jar spigot.jar
And my stop script:
#!/bin/sh
screen -r server stop
Now , the problem is that this script is just accessing the screen without executing that command. I don't want to access the screen then type the "stop" command to stop the server (I mean I don't want to do that myself ) . I want a script which can reattach to my detached screen and execute that command for me. Can you find a solution, please? Oh yeah , and I know it's not important but I want to mention that I am using Spigot 1.12.2
Maybe you can run the command server stop in another script:
#!/bin/sh
screen -r ./Script.sh
------------------------------------
#./Sript.sh
#!/bin/sh
server stop
I'm running a game server on a remote server where I use a detached screen instance to leave it running.
I'm now creating a script that can be used to shut down the server, back up all the vital files and start it up again, however I'm having a few difficulties with dealing with the screen.
I assumed that I could just switch into the detached screen in the script (after the server had already been shut down) by calling screen -r in the script.
But that doesn't seem to work because if I run the script from outside screen it just launches the server in that session.
screen -r
cd ~/servers/StarMade/
sh StarMade-dedicated-server-linux.sh
screen -d
This is what I thought would do the trick but it doesn't. Maybe somebody can help me out here. I'm not a bash expert. In fact this is propably my first bash script that doesn't include "Hello World". Thanks.
Your script, as in your example, will get executed by your sell, not the one in the screen. You need to tell the running screen to read a file and execute it - that's what the -X option is for.
Try
tempfile=$(mktemp)
cat > $tempfile <<EOF
cd ~/servers/StarMade/
sh StarMade-dedicated-server-linux.sh
EOF
screen -X readbuf $tempfile
screen -X paste .
rm -f $tempfile
You can leave screen running in a 2nd terminal session to see what happens.