Cron Job created by script to run another script on reboot - not working

Edward

8/8/24, 7:03 AM

I'm trying to have a script create a cron job that executes another script on reboot. For reasons I am yet to understand, I cannot get this to work.

For the sake of simplicity, this is the snippet I cannot get working.

Script that creates cron job:

#!/bin/bash

crontab /home/user/folder/tmp/crontab-reboot-part-2.txt

Contents of /crontab-reboot-part-2:

@reboot /home/user/folder/script.sh >> /home/user/folder/cron.log 2>&1

Even when manually executing the crontab command before the reboot,

crontab /home/user/folder/tmp/crontab-reboot-part-2.txt

on reboot, the job still doesn't run as cron.log hasn't been created.

Any idea?

Thanks.

Edit: Per @Raffa's comment

ls -l /home/user/folder/script.sh outputs:

-rwxrwxr-x 1 user user 585 Aug 8 06:51 20_run_commissioning.sh

journalctl --grep='cron' --no-pager --since='-1hour' outputs:

-- Logs begin at Thu 2023-08-10 05:28:46 UTC, end at Thu 2023-08-10 13:31:09 UTC. --
Aug 10 13:31:04 ubuntu cron[706]: (CRON) INFO (pidfile fd = 3)
Aug 10 13:31:04 uncommissioned cron[706]: (CRON) INFO (Running @reboot jobs)
Aug 10 05:39:09 uncommissioned systemd[1]: cron.service: Succeeded.
-- Reboot --
Aug 10 05:40:06 uncommissioned cron[728]: (CRON) INFO (pidfile fd = 3)
Aug 10 05:40:06 uncommissioned cron[728]: (CRON) INFO (Running @reboot jobs)
Aug 10 05:40:06 uncommissioned CRON[732]: pam_unix(cron:session): session opened for user user by (uid=0)
Aug 10 05:40:06 uncommissioned CRON[766]: (user) CMD (/home/user/commissioning/20_run_commissioning.sh >> /home/user/commissioning/cron.log 2>&1^M)
Aug 10 05:40:06 uncommissioned CRON[732]: (CRON) info (No MTA installed, discarding output)
Aug 10 05:40:06 uncommissioned CRON[732]: pam_unix(cron:session): session closed for user user

1 + 2

command-line

bash

scripts

cron

Raffa

8/8/24, 12:36 PM

What is the output of `ls -l /home/user/folder/script.sh` and what does it contain ... Also, please reboot your system with that cronjob in the crontab and, after reboot, add the output of `journalctl --grep='cron' --no-pager --since='-1hour'` ... Also, I'm not sure if `@reboot` will run in a normal user's crontab as opposed to root's crontab.

Edward

8/10/24, 5:50 AM

@Raffa see edit.

Score:1

Ubuntu

Edward

8/10/24, 6:37 AM

I found the issue. It was the "^M" appended to the end of

Aug 10 05:40:06 uncommissioned CRON[766]: (user) CMD (/home/user/commissioning/20_run_commissioning.sh >> /home/user/commissioning/cron.log 2>&1^M)

from writing this file on my windows machine.

Thanks for the help @Raffa

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