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I recently came to know that using my account not able to crontab on newly installed machine with RHEL 7.9. Because of this I’m not able to schedule jobs and receiving below error whenever I try to edit the crontab to schedule a job.
[Brines ~]$ crontab -e You (Brines) are not allowed to use this program (crontab) See crontab(1) for more information
Which means we have not configured the crontab after the OS installation.
Basically, Crontab will check for below two files when you are trying to schedule a job using cron.
/etc/cron.allow
/etc/cron.deny
First system will check for cron.allow, if the it is not available/not configured then, it will check for cron.deny neither file exist/not configured then, system will allow only root user to use cron scheduler to schedule a job.
Finally in order to allow a normal user to use crontab, We have to add the username in /etc/cron.allow file and then we are free to use the scheduler.
below is the example:
#vi /etc/cron.allow
lbcuser < newly added user
:wq
or
#echo "lbcuser" >> /etc/cron.allow