Having problems running python script even when putty is closed - linux

So basically, I have a bot I'm running, and I would like for it to keep running even when I exit putty.
I've tried using nohup python bot.py & but it still ends the python bot when I close the putty program. I've also tried using a run.sh file with /usr/bin/nohup bot.py & inside it. but it won't work :( is there something else I'm missing?
I have also made sure the run.sh is a executable as some other forums have suggested, and I still get can't open run
I'm kinda new to the linux terminal.
if you guys could help me out that would be awsome :)

You need to detach the terminal so that when you exit, it is still running. You can use screen or tmux or some other multiplexer.
Here is how to do with screen:
screen -S mybot -m -d /usr/bin/python /path/to/bot.py
-S give the session a name (this is useful if you want to attach later. screen -D -R mybot)
-m always create a new session
-d detach (launch the program, but then detach the terminal returning you to the prompt)

Related

Is there a way to make crontab run a gnu screen session?

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

Need a good way to ssh into a pc and run tmux

I want to SSH into a pc from python code and start tmux and attach to the session and run my programs.
I tryd useing paramiko, if i run tmux it crasched beacause it could not attach to session. Only way i could create a session in paramiko is to run
"tmux new-session -s <pannel name> -d"
but problem is still that i cant attach to the session useing
tmux a
The solution i have atm is autopygui python library and useing putty to start the process this solution works, but i need a better solution.
Found an solution on stackexchange since i cant find it on stack overflow i will post it here.
as part of the question with SSH i used paramiko, template here for the paramiko SSH code. In commands array just enter the tmux commands below.
for terminal commands i used
Create a detached session:
tmux new -d -s mySession
Execute a command in the detached session:
tmux send-keys -t mySession.0 "echo 'Hello World'" ENTER
3.1 Attach to the session
`tmux a -t mySession`
3.2 To exit SSH terminal
exit
Solution explanation:
Paramiko can't attach/jump to the new session with paramiko so solution is to use sendkeys in detached mode to execute commands.

Run a shell script in Terminal through a keyboard/desktop shortcut

I'm using Linux (Mint 20.3) to run a simple Minecraft server and I want to be able to start the server with a keyboard or desktop shortcut. I also want to be able to interact with the server in a terminal after it starts. I'm currently using the server software supplied by Mojang. I wrote a little program to get things started:
#!/bin/bash
cd /home/trevor/Minecraft_Server
LD_LIBRARY_PATH=. ./bedrock_server
exec $SHELL
I can get the server to run but I have no clue how to get it to open a terminal window so I can interact with the server. I'm relatively new to Linux so any input would be greatly appreciated.
you can use screen to detach and attach to run commands into the minecraft terminal.
to install screen:
apt-get install -y screen
To launch, update your script with something like:
screen -S mcs ./bedrock_server
to reattach, run the following in a terminal:
screen -r mcs
Use screen in your script to reattach to bedrock process.
Install screen:
apt-get install screen
Define your script as:
#!/bin/bash
export LD_LIBRARY_PATH=.
cd /home/trevor/Minecraft_Server
screen -d -m -S bedrock ./bedrock_server
After invoke your script, screen creates a socket that can be used to reattach to your script terminal. You can show screen sockets available with:
screen -ls
Parameter -S defined 'bedrock' as the socket name. So you can open another terminal as you like and reattach to the bedrock process with:
screen -r bedrock
If you detach the screen with CTRL+C the screen will be closed and so the minecraft bedrock server. To deattach without close the process you must use CTRL+A and CTRL+D.

create screen session that doesn't terminate with the program

I'm working on a startup script that is initiated from rc.local. I start up several programs with
screen -d -m my-prog
and that works great. However, if one of the programs has problems and exits, so does the session. I'd like to be able to have the session stick around so I can attach to it and see the output from the program before it crashed.
Is there a way to do this? I thought about
screen -d -m bash -c my-prog
But again, if my-prog terminates then so does bash and then so does screen.
You can follow the answer at https://unix.stackexchange.com/questions/47271/prevent-gnu-screen-from-terminating-session-once-executed-script-ends
They suggest something like you were trying in your second attempt, but instead of using bash to invoke the command (which terminates with the command as you noted), invoke bash after the command finishes like:
screen -dmS session_name sh -c 'my-prog; exec bash'

Run a script after killing lxsession (xorg)

I am trying to run a program automatically within a bash script after killing the LXDE session. My script consists of:
#!/bin/sh
pkill lxsession;
sh /home/pi/RetroPie/EmulationStation/emulationstation
I tried this as well:
#!/bin/sh
nohup & pkill lxsession &
writevt /dev/tty1 'emulationstation'
My aim is to log out of the LXDE session and run EmulationStation on my Raspberry Pi with a bash script. I'm using pkill lxsession; to bypass lxsession's logout confirmation dialog.
As it stands, this script just gets me to the command line from a working LXDE desktop. Thanks for reading.
Dont EmulationStation need some sort of X server running in the background for it to work?
IF not, then try the following:
#!/bin/sh
pkill lxsession;
sleep 5
su -c sh /home/pi/RetroPie/EmulationStation/emulationstation
exit
It could also be that when you log out of your lxde session the emulationstation dosent have a usershell to open it, therefore "su -c"
I'm not sure if its going to work but I hope you solve it. :)

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