Which file contains the list of users allowed to run cron jobs on a Linux system?

• A. /etc/cron.deny
• B. /etc/crontab
• C. /etc/cron.allow
• D. /etc/hosts.allow

Answer: (C)

Cron access control relies on two files: /etc/cron.allow and /etc/cron.deny. If the allow file exists, only users listed there are permitted to run crontab, making /etc/cron.allow the file that specifies who can run cron jobs. The deny file serves as a blacklist, usually consulted only when the allow file is not present, to deny specific users from cron. The other paths shown aren’t about per-user cron permissions: /etc/crontab is the system-wide schedule file, not a per-user authorization list, and /etc/hosts.allow is for TCP wrappers and network service access, not cron. Therefore, the correct file is /etc/cron.allow.