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.
Related
I have a script that I would like to run as service on my Linux machine, let's call it my_script.sh. It is executable and can be run over ./path/to/my_scrit.sh.
I also have script that kills my_script.sh, let's call it kill_my_scprit.sh. The contents of kill_my_script.sh are:
#!/bin/bash
sudo kill -SIGINT $(pgrep my_script)
In essence, this should mimic Ctrl+C for my_script.sh.
This works perfectly fine if I run the scripts from a terminal, i.e. in ttyX I run ./path/to/my_scrit.sh to start it and in ttyY ./path/to/kill_my_scrit.sh to initiate the shut down sequence of my_script.sh.
As mentioned before, the goal is to run this as deamon, so I created /etc/systemd/system/my_script.service
[Unit]
....
[Service]
Type=simple
User=root
WorkingDirectory=/path/to/dir/
ExecStart=/path/to/my_script.sh
ExecStop=/path/to/kill_my_script.sh
Restart=on-failure
[Install]
...
Using sudo systemctl start my_script.service starts the script as expected, but using sudo systemctl stop my_script.service starts the shutdown sequence for my_script.sh, but doesn't let it finish... Am I missing something? The shutdown sequence takes roughly 10sec...
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.
I have the following problem using bash script.
Here is what I have inside the 'startup' script file:
#!/bin/bash
java -cp ../lib/online-store.jar:../lib/* com.online.store.Main
OnlineStorePID=$!
if [$OnlineStorePID -ne 0] then
echo "kill $OnlineStorePID" > shutdown
fi
Basically what I do, is to run a java application, get the process id and write it to another bash file. All this process works when I execute the startup script, and the 'shutdown' script file is updated successfully with a line containing 'kill processIDNumber' cmd.
Now I have tried to create a service on Ubuntu for this script using the following commands:
sudo systemctl daemon-reload
sudo systemctl enable online-store.service
sudo systemctl start online-store
When I start the service the java application starts successfully, but the shutdown script file is not updated. It seems that the 'echo "kill $OnlineStorePID" > shutdown' line is not executed. I don't get any complain errors. Does anyone knows what's the problem here.
Here is my service file:
[Unit]
Description=Online store service
Requires=multi-user.target
After=multi-user.target
Wants=mysql.service
[Service]
WorkingDirectory=/home/user/Desktop/online-store-service
#path to executable.
ExecStart=/home/user/Desktop/online-store-service/bin/startup
ExecStop=/home/user/Desktop/online-store-service/bin/shutdown
SuccessExitStatus=143
TimeoutStopSec=10
Restart=on-failure
RestartSec=5
[Install]
WantedBy=multi-user.target
Change your script and run the java command like below as back ground process
java -cp ../lib/online-store.jar:../lib/* com.online.store.Main >/dev/null 2>&1 &
I’m trying to configure my host during deployment process and to give an output to the screen of what my configuration script is doing.
In RHEL6 it was easy i was echoing what I want to screen or used dialog to display the output, and only when my script was done i got the login prompt.
( I used rc3.d or rc5.d folder with script name S99.myscript.sh)
In RHEL7 i can’t mimic this process.
rc.local does not display my output during booting and also its not guaranteed it will run last.
I guess I need to create a systemd service file that will run my script.
But how do I output the result to the screen while booting?
And how do I make sure I will not get the log-in prompt before my script ends?
below service example works like a charm :)
[Unit]
Description=ldt_bootscript1.service
After=network.target
Before=getty#tty1.service
[Service]
Type=oneshot
ExecStart=/bin/bash -c "/bin/bash /tmp/ldt_scripts/postinstall/rc.firstboot.qas | /usr/bin/dialog --clear --backtitle \"Linux Deployment\" --title \"tests\" --progressbox 20 70 > /dev/console 2>&1"
ExecStartPre=/usr/bin/echo -e \033%G
ExecReload=/bin/kill -HUP $MAINPID
RemainAfterExit=no
WorkingDirectory=/
Environment=TERM=xterm
[Install]
WantedBy=multi-user.target
My script (located in /etc/init.d) is creating a pid file ($PIDFILE), but there is no process running. My daemon script includes:
start-stop-daemon --start --quiet --pidfile $PIDFILE -m -b --startas $DAEMON --test > /dev/null || return 1
The script works fine when executing it manually.
You need to create startup links.
sudo update-rc.d SCRIPT_NAME defaults
then reboot. SCRIPT_NAME is the name of the script in /etc/init.d (Without the path)
Was able to get it working, but tried so many things, don't know exactly what fixed it (probably an error in script or config). However, learned a lot and wanted to share since I can't find much of the same in the internet abyss.
It seems Ubuntu (and many other distros based on Ubuntu, including Mint) has migrated to Upstart for job and service management. Upstart includes SysVinit (using /etc/init.d daemons) compatibility that still can use update-rc.d to manage daemons (so if you are familiar with that usage, you can keep on using it). The Upstart method is to use a single .conf file in the /etc/init folder. My SCRIPT.conf file is very simple (I'm using a python script):
start on filesystem or runlevel [2345]
stop on runlevel [016]
exec python /usr/share/python-support/SCRIPT/SCRIPT.py
This simple file completely replaces the standard script in /etc/init.d with the case statement to provide [start|stop|restart|reload] functions and the pointer to /usr/bin/SCRIPT. You can see that it includes runlevel control that would normally be found in the /etc/rc*.d files (thus eliminating several files).
I tried update-rc.d to create the necessary /etc/rc*.d/ files for my daemon. My daemon bash script is located in /etc/init.d and includes the start-stop-daemon command as in my original question. (That command also works fine from terminal.)
I had /etc/rc*.d/ files, the bash script in /etc/init.d and /etc/init/SCRIPT.conf file during boot and it seems that Upstart likely first looks for the .conf file for its direction because the SysVinit command service SCRIPT [start|stop|restart|reload] returns Unknown Instance, however you can find the process is running with ps -elf | grep SCRIPT_FILE.
One interesting thing to note is the forking of your daemon when using .conf. The script as written above only spawns one fork of the daemon. However, total independence of the original script is possible by using expect fork or expect daemon and respawn (see the Upstart Cookbook for reference). Using these will ensure that your daemon will never be killed (at least by using the kill command).
I continued to test both my daemon and the boot process by utilizing the sudo initctl reload-configuration command. This reloads the conf files where you can test your daemon by the sudo [start|stop|restart] SCRIPT command. The result of the start command is:
$ sudo start SCRIPT
SCRIPT start/running, process xxxx
$ sudo restart SCRIPT
SCRIPT start/running, process xxxx
$ sudo stop SCRIPT
SCRIPT stop/waiting
Also, there is a nice log in /var/log/upstart/SCRIPT.log that gives you useful information for your daemon during boot. Mine still has a very annoying bug that prevents root from displaying osd messages with notify-send from my daemon. My log file includes a gtk warning (I will open another question to solicit help).
Hope this helps others in developing their daemons.