I want to create a service called anything.service that downloads and executes a remote script ever 10 seconds I can create the timer but the service isn't executing the script.
Does anyone know how to achieve this?
I'm looking for it to contain something along the lines of:
ExecStart=/usr/bin/bash "wget -O- http://server.com/script.sh | sh"
I can run this script by calling it with
ExecStart=/usr/bin/bash /etc/systemd/system/.script
But I'm looking for a way to run the line within the anything.service file.
Related
I have this myscript.sh act as a performance monitor in Windows Server. To do so, I'm using Git Bash to run the script but the problem is the script just execute it once after I put the command to run it. Is there any command that I can use to run it in daemon or maybe let the script run periodically based on our time interval?
I've been writing Bash scripts that work with a database lately.
To access the database, I need to ssh into a DiskStation (requires password) and then sudo a docker command (requires password) to access the container that the database is in. Only then can I execute and test out my scripts.
I wrote an expect script that automates this process and I want to embed it in my Bash scripts, but the only problem is the shell closes as soon as the expect script finishes executing.
Does anybody know how to work around this? I attached a photo with specific info removed. Bash script with embedded expect script
I have a python script that get started automatically as a service (activated with systemd). In this python script, I call a bash script using subprocess.call(script_file,shell=True).
When I call the python script manually ($ python my_python_script.py), everything works perfectly. However, the automatically started program does not execute the bash script (however it does run, I checked this my making it edit a text file, which it indeed does).
I (think) I gave everyone read-write permissions to the bash scripts. Does anyone have ideas as to what I'm doing wrong?
Addendum: I want to write a small script that sends me my public IP address via telegram. The service file looks like this:
[Unit]
Description=IPsender
After=networking.service
[Service]
Type=simple
User=root
WorkingDirectory=/home/pi/projects/tg_bot
ExecStart=/home/pi/miniconda3/bin/python /home/pi/projects/tg_bot/ip_sender_tg.py
Restart=always
[Install]
WantedBy=multi-user.target
Protawn, welcome to the Unix and Linux StackExchange.
Why scripts work differently under system is a common question. Check out this answer to the general question elsewhere on the site.
Without the source code for your Python and Bash scripts it's hard to guess which difference you have encountered.
My personal guess is that your bash script is calling some other binaries without full paths, and those paths are found in your shell $PATH but not the default systemd path.
Add set -x to the top of your bash script so that all actions are logged to standard out, which will be captured in the systemd journal. Then after it fails, use journalctl -u your-service-name to view the logs for your service to see if you can find the last command that bash executed successfully. Also consider using set -e in the bash script to have it stop at the first error.
Despite the two "off-topic" "close" votes on this topic, why things work differently under systemd is on topic for this Stack Exchange site.
I am on shared hosting and I'm trying to schedule cronjob to run every now and then. Via cPanel I scheduled to execute my script but even though that according to my host support the cronjob runs, the script doesn't seem as doing anything. The cron job command I set via cPanel is:
/bin/sh /home1/myusername/public_html/somefolder/cronjob2.sh
and the cronjob2.sh
#!/bin/bash
/home1/myusername/public_html/somefolder/node_modules/forever/bin/forever stop 0
when via SSH I execute:
/home1/myusername/public_html/somefolder/cronjob2.sh
it stops forever process as needed. From cronjob doesn't do anything.
How can I get this working?
EDIT:
So I've tried:
/bin/sh /home1/username/public_html/somefolder/cronjob2.sh >> /tmp/mylog 2>&1
and mylog entries say:
/usr/bin/env: node: No such file or directory
It seems that forever needs to run node and this cannot be found. How would I possibly fix this?
EDIT2:
Accepted answer at superuser.com. Thank you all for help
https://superuser.com/questions/763261/simple-script-run-via-cronjob-doesnt-work-but-works-from-shell/763288#763288
For cron job lines in a crontab it's not required to specify kind of shell or e.g. of perl.
It's enough, that your script contains
shebang
line.
Therefore you should remove /bin/sh from your cron job line.
Another aspect, that might cause a different behavior of your script by interactive start and by cron daemon start is possible different environment, first of all the PATH variable. Therefore check, if you script is able to be executed in very restricted environment, that is provided by cron daemon. You can determine your cron job environment experimentally by start of temporary cron job, that executes "env" command and writes its output to a file.
Once more aspect: Have you redirected STDOUT and STDERR of the cron job to a log file and read its content to analyze the issue? You can do it as follows:
your_cron_job >/tmp/any_name.log 2>&1
According to what you wrote, when you run your script via SSH, you are using bash, because this line is the first of your script:
#!/bin/bash
However, in the crontab, you are forcing the use of sh instead of bash. Are you sure your script is fully compatible with sh? Otherwise, simply replace /bin/sh with /bin/bash in your cron command and test again.
I have a program that runs as a daemon, using the C command fork(). It creates a new instance that runs in the background. The main instance exists after that.
What would be the best option to check if the service is running? I'm considering:
Create a file with the process id of the program and check if it's running with a script.
Use ps | grep to find the program in the running proccess list.
Thanks.
I think it will be better to manage your process with supervisord, or other process control system.
Create a cron job that runs every few minutes (or whatever you're comfortable with) and does something like this:
/path/to/is_script_stopped.sh && /path/to/script.sh
Write is_script_stopped.sh using any of the methods that you suggest. If your script is stopped cron will evaluate your script, if not, it won't.
To the question, you gave in the headline:
This simple endless loop will restart yourProgram as soon as it fails:
#!/bin/bash
for ((;;))
do
yourProgram
done
If your program depends on a resource, which might fail, it would be wise to insert a short pause, to avoid, that it will catch all system resources when failing million times per second:
#!/bin/bash
for ((;;))
do
yourProgram
sleep 1
done
To the question from the body of your post:
What would be the best option to check if the service is running?
If your ps has a -C option (like the Linux ps) you would prefer that over a ps ax | grep combination.
ps -C yourProgram