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 want to run the command webscreenshot automatically (project found at https://pypi.org/project/webscreenshot/#description).
This command should run via cron task or systemd automatically, every 15 minutes.
Running a linux server with python3.6, I've tried to incorporate this as a cron task but it is failing. Should I create my own python script to automate this?
*/1 * * * * /usr/bin/python3.6 /home/user/.local/bin/webscreenshot -i /home/user/projects/webscreenshot/data.txt -o /home/user/projects/webscreenshot/screenshots > /home/user/projects/log.txt 2>&1
I expect this to run the python script webscreenshot but this is not the case, screenshots are not produced.
#Ari - the .py extension is left out by the default installation.
I was able to get this to work by adding
xvfb-run to the begging, to read:
xvfb-run /dir/to/webscreenshot -i file.txt -o /output/dir/screenshots
I am writing a shell script so when my raspberry pi is turned on it automatically runs a shell script that starts two programs running one in the background and the other not.
My code:
#!/bin/bash
cd rpi2ardu/
sudo ./Main
Then I want that first program to run in background done by the shell script - how do I do this?
The next program:
java -cp ".:someLib:someLib" myprog
These will all be incorporated into the same shell script but as you can probably notice this isn't working. I am new to raspberry pi and linux so any help would be great thanks.
Log in as root
First you make a file in /etc/init.d called mystartup.sh
You need to make it executable via chmod +x /etc/init.d/mystartup.sh
Set it up to run at boot with update-rc.d mystartup.sh defaults 100
edit mystartup.sh and append /path/to/file.sh and save
You can add an & at the end of the first command:
#!/bin/bash
cd rpi2ardu/
sudo ./Main &
java -cp ".:someLib:someLib" myprog
be careful, java will be executed regardless of the Main status, this is not safe if the second program is dependent from the first one
On an Amazon S3 Linux instance, I have two scripts called start_my_app and stop_my_app which start and stop forever (which in turn runs my Node.js application). I use these scripts to manually start and stop my Node.js application. So far so good.
My problem: I also want to set it up such that start_my_app is run whenever the system boots up. I know that I need to add a file inside init.d and I know how to symlink it to the proper directory within rc.d, but I can't figure out what actually needs to go inside the file that I place in init.d. I'm thinking it should be just one line, like, start_my_app, but that hasn't been working for me.
First create your startup script # /home/user/startup.sh, and make it executable
chmod +x /home/user/startup.sh
Then set a crontab for it:
$ crontab -e
#reboot /home/user/startup.sh
Now your your startup.sh script will run at every start.
The file you put in /etc/init.d/ have to be set to executable with:
chmod +x /etc/init.d/start_my_app
As pointed out by #meetamit, if it still does not run you might have to create a symbolic link to the file in /etc/rc.d/
ln -s /etc/init.d/start_my_app /etc/rc.d/
Please note that on the latest versions of Debian, this will not work as your script will have to be LSB compliant (provide at least the following actions: start, stop, restart, force-reload, and status):
https://wiki.debian.org/LSBInitScripts
As a note, you should always use the absolute path to files in your scripts instead of the relative one, it may solve unexpected issues:
/var/myscripts/start_my_app
Finally, make sure that you included the shebang on top of the file:
#!/bin/sh
A simple approach is to add a line in /etc/rc.local :
/PATH/TO/MY_APP &
or if you want to run the command as a special user :
su - USER_FOOBAR -c /PATH/TO/MY_APP &
(the trailing ampersand backgrounds the process and allows the rc.local to continue executing)
If you want a full init script, debian distro have a template file, so :
cp /etc/init.d/skeleton /etc/init.d/your_app
and adapt it a bit.
This is the way I do it on Red Hat Linux systems.
Put your script in /etc/init.d, owned by root and executable. At the top of the script, you can give a directive for chkconfig. Example, the following script is used to start a Java application as user oracle.
The name of the script is /etc/init.d/apex
#!/bin/bash
# chkconfig: 345 99 10
# Description: auto start apex listener
#
case "$1" in
'start')
su - oracle -c "cd /opt/apex ; java -jar apex.war > logs/apex.log 2>logs/apex_error.log &";;
'stop')
echo "put something to shutdown or kill the process here";;
esac
This says that the script must run at levels 3, 4, and 5, and the priority for start/stop is 99 and 10.
Then, as user root you can use chkconfig to enable or disable the script at startup:
chkconfig --list apex
chkconfig --add apex
And you can use service start/stop apex.
Enter cron using sudo:
sudo crontab -e
Add a command to run upon start up, in this case a script:
#reboot sh /home/user/test.sh
Save:
Press ESC then :x to save and exit, or hit ESC then ZZ (that's shift+zz)
Test Test Test:
Run your test script without cron to make sure it actually works.
Make sure you saved your command in cron, use sudo crontab -e
Reboot the server to confirm it all works sudo #reboot
Just have a line added to your crontab..
Make sure the file is executable:
chmod +x /path_to_you_file/your_file
To edit crontab file:
crontab -e
Line you have to add:
#reboot /path_to_you_file/your_file
That simple!
Another option is to have an #reboot command in your crontab.
Not every version of cron supports this, but if your instance is based on the Amazon Linux AMI then it will work.
Edit the rc.local file using nano or gedit editor and add your scripts in it. File path could be /etc/rc.local or /etc/rc.d/rc.local.
sudo nano /etc/rc.local
This is the edit:
#!/bin/sh
/path-to-your-script/your-scipt-name.sh
once done press ctrl+o to update, pressEnter then ctrl+x.
Make the file executable.
sudo chmod 755 /etc/rc.local
Then initiate the rc-local service to run script during boot.
sudo systemctl start rc-local
You can do it :
chmod +x PATH_TO_YOUR_SCRIPT/start_my_app
then use this command
update-rc.d start_my_app defaults 100
Please see this page on Cyberciti.
Many answers on starting something at boot, but often you want to start it just a little later, because your script depends on e.g. networking. Use at to just add this delay, e.g.:
at now + 1 min -f /path/yourscript
You may add this in /etc/rc.local, but also in cron like:
# crontab -e
#reboot at now + 1 min -f /path/yourscript
Isn't it fun to combine cron and at? Info is in the man page man at.
As for the comments that #reboot may not be widely supported, just try it. I found out that /etc/rc.local has become obsolete on distros that support systemd, such as ubuntu and raspbian.
The absolute easiest method if all you want to run is a simple script, (or anything) is if you have a gui to use system > preferences then startup apps.
just browse to the script you want and there you go. (make script executable)
This simple solution worked for me on an Amazon Linux instance running CentOS.
Edit your /etc/rc.d/rc.local file and put the command there. It is mentioned in this file that it will be executed after all other init scripts. So be careful in that regards. This is how the file looks for me currently.. Last line is the name of my script.
Create your own /init executable
This is not what you want, but it is fun!
Just pick an arbitrary executable file, even a shell script, and boot the kernel with the command line parameter:
init=/path/to/myinit
Towards the end of boot, the Linux kernel runs the first userspace executable at the given path.
Several projects provide popular init executables used by major distros, e.g. systemd, and in most distros init will fork a bunch of processes used in normal system operation.
But we can hijack /init it to run our own minimal scripts to better understand our system.
Here is a minimal reproducible setup: https://github.com/cirosantilli/linux-kernel-module-cheat/tree/f96d4d55c9caa7c0862991025e1291c48c33e3d9/README.md#custom-init
I refered to this blog, always sound a good choice
https://blog.xyzio.com/2016/06/14/setting-up-a-golang-website-to-autorun-on-ubuntu-using-systemd/
vim /lib/systemd/system/gosite.service
Description=A simple go website
ConditionPathExists=/home/user/bin/gosite
[Service]
Restart=always
RestartSec=3
ExecStart=/home/user/bin/gosite
[Install]
WantedBy=multi-user.target
systemctl enable gosite.service
multi ways to finish it:
crontab
rc.local
init.d
systemd
For Debian 9 see https://askubuntu.com/questions/228304/how-do-i-run-a-script-at-start-up. It is helped me. Short version for Debian 9:
add commands (as root) to /etc/rc.local
/path_to_file/filename.sh || exit 1 # Added by me
exit 0
Probably, /path_to_file/filename.sh should be executable (I think so).
In Lubuntu I had to deal with the opposite situation. Skype start running after booting and I found in ~/.config/autostart/ the file skypeforlinux.desktop. The content of the file is as follows:
[Desktop Entry]
Name=Skype for Linux
Comment=Skype Internet Telephony
Exec=/usr/bin/skypeforlinux
Icon=skypeforlinux
Terminal=false
Type=Application
StartupNotify=false
X-GNOME-Autostart-enabled=true
Deleting this file helped me.
Here is a simpler method!
First: write a shell script and save it a .sh
here is an example
#!/bin/bash
Icoff='/home/akbar/keyboardONOFF/icon/Dt6hQ.png'
id=13
fconfig=".keyboard"
echo "disabled" > $fconfig
xinput float $id
notify-send -i $Icoff "Internal Keyboard disabled";
this script will disable the internal keyboard at startup.
Second: Open the application " Startup Application Preferences"
enter image description here
enter image description here
Third: click Add.
fourth: in the NAME section give a name.
fifth: In the command section browse to your .sh .
sixth: edit your command section to:
bash <space> path/to/file/<filename>.sh <space> --start
seventh: click Add. Thats it! Finished!
Now confirm by rebooting your pc.
cheers!
Add your script to /etc/init.d/ directory
Update your rc run-levels:
$ update-rc.d myScript.sh defaults NN where NN is the order in which it should be executed. 99 for example will mean it would be run after 98 and before 100.
Painless, easiest and the most universal method is simply
executing it with ~.bash_profile or ~.profile (if you don't have bash_profile file).
Just add the execution command at the bottom of that file and it will be executed when system started.
I have this one at the bottom an example;
~\Desktop\sound_fixer.sh
Working with Python 3 microservices or shell; using Ubuntu Server 18.04 (Bionic Beaver) or Ubuntu 19.10 (Eoan Ermine) or Ubuntu 18.10 (Cosmic Cuttlefish) I always do like these steps, and it worked always too:
Creating a microservice called p example "brain_microservice1.service" in my case:
$ nano /lib/systemd/system/brain_microservice1.service
Inside this new service that you are in:
[Unit]
Description=brain_microservice_1
After=multi-user.target
[Service]
Type=simple
ExecStart=/usr/bin/python3.7 /root/scriptsPython/RUN_SERVICES/microservices /microservice_1.py -k start -DFOREGROUND
ExecStop=/usr/bin/python3.7 /root/scriptsPython/RUN_SERVICES/microservices/microservice_1.py -k graceful-stop
ExecReload=/usr/bin/python3.7 /root/scriptsPython/RUN_SERVICES/microservices/microservice_1.py -k graceful
PrivateTmp=true
LimitNOFILE=infinity
KillMode=mixed
Restart=on-failure
RestartSec=5s
[Install]
WantedBy=multi-user.target
Give the permissions:
$ chmod -X /lib/systemd/system/brain_microservice*
$ chmod -R 775 /lib/systemd/system/brain_microservice*
Give the execution permission then:
$ systemctl daemon-reload
Enable then, this will make then always start on startup
$ systemctl enable brain_microservice1.service
Then you can test it;
$ sudo reboot now
Finish = SUCCESS!!
This can be done with the same body script to run shell, react ... database startup script ... any kind os code ... hope this help u...
...
For some people, this will work:
You could simply add the following command into System → Preferences → Startup Applications:
bash /full/path/to/your/script.sh