I have a Python file that needs to be constantly running (a Telegram bot), but if I run in the background
python bot.py &
and then gracefully end the SSH connection, after a while the bot stops responding and I have to connect and launch it again.
How can I stop this from happening? If i cannot, how can I check when it is dead and relaunch it?
chmod +x bot.py
Do this to your python file to make it executable
nohup /path/to/script/bot.py &
The nohup will run the script in the background while the & will keep it running after you close the terminal
To check if your script is still running ps -e | grep bot.py
To see any errors run cat nohup.out
Related
I have set up Flask on my Rapsberry Pi and I am using it for the sole purpose of acting as a server for an xml file which I created with a Python script to pass data to an iPad app (iRule).
My RPI is set up as headless and my access is with Windows 10 using PuTTY, WinSCP and TightVNC Viewer.
I run the server by opening a terminal window and the following command:
sudo python app1c.py
This sets up the server and I can access my xml file quite well. However, when I turn off the Windows machine and the PuTTY session, the Flask server shuts down!
How can I set it up so that the Flask server continues even when the Windows machine is turned off?
I read in the Flask documentation:
While lightweight and easy to use, Flask’s built-in server is not suitable for production as it doesn’t scale well and by default serves only one request at a time.
Then they go on to give examples of how to deploy your Flask application to a WSGI server! Is this necessary given the simple application I am dealing with?
Use:
$ sudo nohup python app1c.py > log.txt 2>&1 &
nohup allows to run command/process or shell script that can continue running in the background after you log out from a shell.
> log.txt: it forword the output to this file.
2>&1: move all the stderr to stdout.
The final & allows you to run a command/process in background on the current shell.
Install Node package forever at here https://www.npmjs.com/package/forever
Then use
forever start -c python your_script.py
to start your script in the background. Later you can use
forever stop your_script.py
to stop the script
You have multiple options:
Easy: deattach the process with &, for example:
$ sudo python app1c.py &
Medium: install tmux with apt-get install tmux
launch tmux and start your app as before and detach with CTRL+B.
Complexer:
Read run your flask script with a wsgi server - uwsgi, gunicorn, nginx.
Been stressing lately so I decide to go deep.
pm2 start app.py --interpreter python3
Use PM2 for things like this. I also use it for NodeJs app and a Python app on a single server.
Use:
$sudo python app1c.py >> log.txt 2>&1 &
">> log.txt" pushes all your stdout inside the log.txt file (You may check the application logs in it)
"2>&1" pushes all the stderr inside the log.txt file (This would push all the error logs inside log.txt)
"&" at the end makes it run in the background.
You would get the process id immediately after executing this command with which you can monitor or verify it.
$sudo ps -ef | grep <process-id>
Hope it helps..!!
You can always use nohup to run any scripts as background process.
nohup python script.py
This will run your script in background and also have its logs appended in nohup.out file which will be located in the directory script.py is store.
Make sure, you close the terminal and not press Ctrl + C. This will allow it to run in background even when you log out.
To stop it from running , ssh in to the pi again and run ps -ef |grep nohup and kill -9 XXXXX
where XXXX is the pid you will get ps command.
I've always found a detached screen process to be best for use cases such as these.
Run:
screen -m -d sudo python app1c.py
I was trying to run my flask app for testing in my GitHub CI and the step where I was running the app was getting stuck for ever. The reason was that it was never releasing the command line
Best solution I found was a combination of two other responses in here:
nohup python script.py &
I have a django project hosted on an amazon ec2 linux instance.
For run my app also when section is close i use gunicorn but i experience some errors and degradation in perfonrmances.
When i run command:
python manage.py runserver
from terminal all works great but when section is close app does not work.
How can i run command "python manage.py runserver" for work forever (until i'll kill it) in background also in case of closed session?
I know there is uWSGI but i prefer if possible use directly django native command.
Thanks in advance
What happens here is that the script is interrupted by SIGHUP signal when your session is closed. To overcome this problem, there is a tool called nohup which doesn't pass the SIGHUP down to the program/script it executes. Use it as follows:
nohup python manage.py runserver &
(note the & in the end, it is needed so that manage.py runs in background rather than in foreground).
By default nohup redirects the output in the file nohup.out, so you can use tail -f nohup.out to watch the output/logs of your Django app.
Note, however, that manage.py runserver is not supposed to be used in production. For production you really should use a proper WSGI server, such as uWSGI or Gunicorn.
You can install and use tmux if you want to run your scripts in background even after closing SSH and mosh connections
$ sudo apt-get install tmux
then run it using command $ tmux a new shell will be opened just execute your command
$ python manage.py runserver 0.0.0.0:8000
0.0.0.0:8000 here will automatically get your allowed hosts. Now you can detach your tmux session to run it in background using CTRL + B and then press D
Now you can exit your terminal but your command keep on running in tmux. Just learn basic commands to use tmux from here
for that, you can use screen just start a new screen and run
python manage.py runserver
I am trying to run this Python Script on a Digital Ocean (DO) Droplet (Ubuntu 16):
https://github.com/instabot-py/instabot.py
Although I can run python3 example.py the process stops if I kill the Terminal windown I used to SSH into the DO Droplet.
Is there a way to run this Python script and disconnect from the DO Droplet with the Python script still running?
Use nohup to run program in background
nohup python3 example.py > /dev/null 2>&1 &
Or you can use screen to do this:
$ screen
$ python3 example.py
To detach the current session, you can press Ctrl+A and then press D.
To re-attach previous session, use command `screen -r`
The screen command is more powerful than nohup.
You can use screen in linux to continue executing the process in background even after you disconnect from server.
Similarly tmux can be used.
The answer to this question is most probably what you are looking for.
You can try these python library to achieve this
http://www.paramiko.org/
https://pypi.python.org/pypi/spur
Or you can also use tmux to run command on remote server and your tmux seisson will run in the background even if you quit the shell. You can join that tmux session even after days and continue executing command
We use the following format to execute remote script
ssh -t -t user#host.com 'nohup /path/to/scrip.py'
I have set up Flask on my Rapsberry Pi and I am using it for the sole purpose of acting as a server for an xml file which I created with a Python script to pass data to an iPad app (iRule).
My RPI is set up as headless and my access is with Windows 10 using PuTTY, WinSCP and TightVNC Viewer.
I run the server by opening a terminal window and the following command:
sudo python app1c.py
This sets up the server and I can access my xml file quite well. However, when I turn off the Windows machine and the PuTTY session, the Flask server shuts down!
How can I set it up so that the Flask server continues even when the Windows machine is turned off?
I read in the Flask documentation:
While lightweight and easy to use, Flask’s built-in server is not suitable for production as it doesn’t scale well and by default serves only one request at a time.
Then they go on to give examples of how to deploy your Flask application to a WSGI server! Is this necessary given the simple application I am dealing with?
Use:
$ sudo nohup python app1c.py > log.txt 2>&1 &
nohup allows to run command/process or shell script that can continue running in the background after you log out from a shell.
> log.txt: it forword the output to this file.
2>&1: move all the stderr to stdout.
The final & allows you to run a command/process in background on the current shell.
Install Node package forever at here https://www.npmjs.com/package/forever
Then use
forever start -c python your_script.py
to start your script in the background. Later you can use
forever stop your_script.py
to stop the script
You have multiple options:
Easy: deattach the process with &, for example:
$ sudo python app1c.py &
Medium: install tmux with apt-get install tmux
launch tmux and start your app as before and detach with CTRL+B.
Complexer:
Read run your flask script with a wsgi server - uwsgi, gunicorn, nginx.
Been stressing lately so I decide to go deep.
pm2 start app.py --interpreter python3
Use PM2 for things like this. I also use it for NodeJs app and a Python app on a single server.
Use:
$sudo python app1c.py >> log.txt 2>&1 &
">> log.txt" pushes all your stdout inside the log.txt file (You may check the application logs in it)
"2>&1" pushes all the stderr inside the log.txt file (This would push all the error logs inside log.txt)
"&" at the end makes it run in the background.
You would get the process id immediately after executing this command with which you can monitor or verify it.
$sudo ps -ef | grep <process-id>
Hope it helps..!!
You can always use nohup to run any scripts as background process.
nohup python script.py
This will run your script in background and also have its logs appended in nohup.out file which will be located in the directory script.py is store.
Make sure, you close the terminal and not press Ctrl + C. This will allow it to run in background even when you log out.
To stop it from running , ssh in to the pi again and run ps -ef |grep nohup and kill -9 XXXXX
where XXXX is the pid you will get ps command.
I've always found a detached screen process to be best for use cases such as these.
Run:
screen -m -d sudo python app1c.py
I was trying to run my flask app for testing in my GitHub CI and the step where I was running the app was getting stuck for ever. The reason was that it was never releasing the command line
Best solution I found was a combination of two other responses in here:
nohup python script.py &
I want to run my python program sent data to server with websocket. I want run my program on booting, so I put my program in crontab with this code :
crontab -e
#reboot /usr/bin/python /usr/local/bin/vcs/vcs.py
#reboot bash /usr/local/bin/vcs/onmodem.sh
in on modem.sh there is the code:
sleep (120)
wvdial &
I got ppp0 but my vcs.py didn't sent any data. Then I try to run my program without booting, my program run and sent data.
How this problem can solved?
Thankyou for the advise
If you want to run your program at startup, I suggest to create a dedicated service.
System and service manager
You can define your service by using the following lines, or directly call you script named modem.sh
ExecStartPre=/bin/sh -c 'sleep 120'
ExecStart=/usr/bin/wvdial &