I have a problem where I am unable to start a screen session at boot using the rc.local file. The specific screen I am starting is for a spigot minecraft server.
This is my rc.local file:
#!/bin/sh -e
#
# rc.local
#
# This script is executed at the end of each multiuser runlevel.
# Make sure that the script will "exit 0" on success or any other
# value on error.
#
# In order to enable or disable this script just change the execution
# bits.
#
# By default this script does nothing.
/home/pi/Documents/bootlog.sh
/home/spigot1_12/startspigot.sh
exit 0
This is the startspigot.sh script (with chmod u+x):
#!/bin/bash
cd /home/spigot1_12
boot=$(date)
echo "Starting spigot server in screen \"minecraft\" # $boot " >> /home/pi/Documents/minecraftlog
screen -S minecraft java -Xms512M -Xmx1008M -jar /home/spigot1_12/spigot-1.12.jar nogui
The minecraftlog file does update at each boot, so the script is run.
When I run the command "sudo sh startspigot.sh", everything works perfectly. The screen is started and the minecraftlog file is updated. I can find the screen again with "sudo screen -ls"
At boot, however, both "sudo screen -ls" and "screen -ls" return no sockets.
What can be causing this? The only two users are "pi" and root.
Thanks in advance!
Starting a script in a new detached screen as current user (rc.local = root):
screen -dmS <session name> <command>, example:
screen -dmS screenName bash /home/user/run.sh
Starting a script from rc.local as user:
runuser -l user -c 'screen -dmS screenName bash /home/user/run.sh'
Running screen in detached mode (when you do not have active terminal, like in rc.local or crontab):
screen -dm -S <session name> <command>
-d -m Start screen in "detached" mode
-S When creating a new session, this option can be used to specify a meaningful name for the session.
Related
I want to create a small startup script that does multiple things in a row in a screen.
The script starts a named, detached screen (screen -S discordbot -d -m works)
The user inside the script is changed (Neither screen -S discordbot -X "su discordbot", screen -S discordbot -X su discordbot, nor screen -S discordbot -d -m bash -c "su discordbot;" seems to work, or at least subsqeuent commands are not executed).
A cd folder change is exectuded.
A java jar or other script is started.
As I run multiple bots, the script needs to be able to do this in slight variation multiple times in a row. Any pointers on how this could be done?
The screen session that you start up will exit as soon as the process that you started exits.
This works, for instance:
$ screen -S discordbot -d -m bash
$ screen -ls
There is a screen on:
2948.discordbot (Detached)
1 Socket in <...>
As does this:
$ screen -S discordbot -d -m bin/discordbot.sh
Where bin/discordbot.sh looks like this:
#!/bin/sh
echo "Sleeping..."
sleep 10
/bin/echo -n "Hit enter to finish this script: "
read
The last two lines to prevent the screen from exiting prematurely. The other various things you want to do within that startup script should also work, assuming that you do this as root so that the su will work without prompting.
I am wanting to run a bash script on startup in Ubuntu 20.04 with the terminal visible. The test.sh file is located at /usr/bin/test.sh. I can get the test.sh file to run at startup but not in a visible terminal window.
Contents of test.sh:
#! /bin/bash
echo "hello";
I can not get it to work, I have tried (individually):
Crontab (with and without the '&' and with/without "sudo")
#reboot bash test.sh &
#reboot /usr/bin/test.sh &
#reboot DISPLAY=:0 xterm -hold -e bash -c "bash test.sh" &
#reboot DISPLAY=:0 xterm -hold -e bash -c "bash /usr/bin/test.sh" &
Startup Applications Command
sudo bash /usr/bin/test.sh
bash /usr/bin/test.sh
/usr/bin/test.sh
Creating a Service at /etc/systemd/system/testService.service
[Unit]
Description = Test Service
[Service]
WorkingDirectory= /usr/bin
ExecStart= /usr/bin/test.sh
[Install]
WantedBy=multi-user.target
And start, enable and checked status..
systemctl start testService.service
systemctl enable testService.service
systemctl status testService.service
But failed to start.
Any help / pointing in a better direction would be appreciated!
To get a GUI terminal window to appear when you run your script:
Add to "Startup Applications" (under command):
bash test.sh
Contents of test.sh:
#! /bin/bash
DISPLAY=:0.0 xterm -hold -e bash helloWorld.sh
Contents of helloWorld.sh:
#! /bin/bash
echo "hello";
For me, this opened an XTerm terminal window upon login and ran the helloWorld.sh script.
When you start a Unix, the X server gets started at the end of the startup. And starting X clients makes only sense, when someone has logged in. So your aim "start X client when computer starts" makes no sense, because there is no X server running when you try to start the X client.
You can start X clients after login. If you use a classical installation, use .xinitrc for this. If you use a different desktop environment, use whatever this desktop environment provides you.
Gnome
KDE
XFCE
I have a game server. It runs on linux via dotnet. I run this inside a 'screen' session.
However I am struggling with restarting this server.
From outside, it is easy. I just kill existing screen via name and create new one.
However when I want to restart server from inside (existing game process starts new process that runs script that kills named screen and starts new one)
To be specific:
stop.sh:
screen -r gameserver -X quit
start.sh:
screen -L -A -m -d -S gameserver /usr/bin/dotnet /gameserver/game.dll
restart.sh:
/gameserver/stop.sh
/gameserver/start.sh
Now If I run restart.sh programmatically from inside screen, it calls stop.sh, which terminates current screen and also this restart.sh script, so the new one is not started.
I tried to run restart.sh via screen:
screen -L -m -d /bin/bash -c /gameserver/restart.sh
But it still doesn't work...
I would expect this to run restart.sh in new screen, where the 'gameserver' screen will terminate and start new one and after that screen running restart.sh will stop. But no :(
Any ideas?
Cant you just kill this process inside the screen?
Something like
screen -r gameserver kill $(ps aux|grep 'game.dll'|awk '{print $2}') ?
I think you probably should NOT run such a script inside screen. Kill the whole session then re-create it inside screen is kind of weird.
And in your script stop.sh, though using -r with -X may sometime work, it doesn't make much sense. I think you should use -S instead of -r.
Run outside screen:
If you replace stop.sh with screen -S gameserver -X quit, and run restart.sh outside screen, it should work.
Run inside screen:
However, if you really need to run it inside screen, you could try to kill a window instead of terminate the whole session.
stop.sh:
# Create a new window before kill 'server'
# Without this, the session will be terminated if 'server' is the only window
screen
screen -p server -X kill
start.sh:
# Are we in the 'gameserver' session?
if [ "${STY#*.}" = gameserver ]; then
# Create a window named 'server' and run your program in it
screen -t server /usr/bin/dotnet /gameserver/game.dll
else
# Create a new screen session named 'gameserver'
# And it's default window is named 'server'
# -T $TERM to make sure things such as '-t' work
screen -L -A -m -d -S gameserver -t server -T $TERM /usr/bin/dotnet /gameserver/game.dll
fi
I'm writing a Linux shell script in which I need to start a new screen session, run a node.js server in the screen, then detach from the screen so that my server runs in the background.
Right now, these are the commands I run manually to do this:
screen
node server.js
[detach screen]
However, I need a way to automate this via the script, and if I just use the above commands in a shell script, it creates the screen and gets stuck there. How can I pass the "node server.js" command to the screen command?
EDIT:
Based on the suggested answer I have a script that works, except that I need to manually create a screen and detach from it before I run it. I tried adding screen -d -m as the first line to create a detached screen, but the script hangs after that line.
tempfile=$(mktemp)
indices=`tail -1 debug.log`
cat > $tempfile <<EOF
node server $indices
EOF
screen -X readbuf $tempfile
screen -X paste .
rm -f $tempfile
How can I create and detach a screen with the script?
This didn't work either:
screen
screen -d
It is as simple as this:
screen -md node server.js
This requires the command to run as a service (as it does), otherwise the screen stops immediately.
To optionally also set a name for the session (e.g. "session-name"):
screen -mdS session-name node server.js
You can then attach to the screen with:
screen -rd session-name
If you want to redirect all output to a file, you can do like this:
screen -mdS session-name bash -c 'node server.js &> output.log'
You can then monitor the output with e.g.:
tail -f output.log
You can list your running screens with:
screen -ls
or
screen -list
Example: Start a Python3 web server in a detached screen
Start a Python3 web server listening on port 8000 that serves files in the current directory, in a named
detached screen:
screen -mdS my-web-server python3 -mhttp.server
Or, with logging to a file:
screen -mdS my-web-server bash -c 'python3 -mhttp.server &> output.log'
For Python 2.x it looks like this:
screen -mdS my-web-server bash -c 'python -mSimpleHTTPServer &> output.log'
EDIT: Try this:
tempfile=$(mktemp)
cat > $tempfile <<EOF
node server.js
EOF
screen -S SessionName -X readbuf $tempfile; screen -RdS SessionName
screen -X paste .
rm -f $tempfile
It should create the temp file, create a screen called SessionName and runs the commands, then delete the temp file. Let me know if that works.
I've tried adding this to my crontab:
#reboot /root/startup
The "startup" file:
#!/bin/sh
svnserve -d -r /root/svnrepos/mainres
svnserve -d -r /root/svnrepos/mapres --listen-port=3691
screen -S mta ./mtaserver/mta-server > log1
screen -S mapmta ./mapserver/mta-server > log2
exit 0
Now svnserve commands run fine. The problem is with the screen command.
log1 and log2 files have the same content which is: Must be connected to a terminal.
What I'm trying to do is start the 2 executables on startup, and then later have a way to access them.
Is there a way to do this?
You want to add the following options to the 'screen' commands (e.g. before -S): -d -m
From the manpage:
-d -m Start screen in "detached" mode. This creates a new session but
doesn't attach to it. This is useful for system startup
scripts.