Looping Shell Script Recipe

1. Change directory to where you would like to store the script output.
2. Create a file named diagscript.sh with contents based on the following:

   #!/bin/sh
   set -e
   outputfile="diag_ps_$(date +"%Y%m%d_%H%M%S").log"
   while true; do
     date >> "${outputfile}" 2>&1
     # Change the command here, update '_ps_' in the file name above to match, and update the example in the next step:
     ps -elfyww >> "${outputfile}" 2>&1
     # Change the sleep time (in seconds) as needed:
     sleep 30
   done

3. Manually confirm the looped command works (as some distributions support different flags). For example:

   ps -elfyww

4. Make the script executable:

   chmod +x diagscript.sh

5. Execute the script with nohup so that it's not interrupted if the user that started the script logs out (on some versions of Linux, you may need systemd-run instead), and send to the background with &:

   nohup ./diagscript.sh &

6. After the script starts in the background, press ENTER to continue with the shell. If you'd like to watch the script output, you may tail it:

   tail -f diag*log

7. When you are ready to stop the script, kill it by finding the process ID and then using that:

   kill ${PID}

   Alternatively, on Linux, use pkill:

   pkill -f diagscript.sh

8. Upload diag*log

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