Hands-on Lab·Red Hat Certified System Administrator
Scheduled Tasks with cron
Part of one objective that names cron, at and timer units together. cron is the oldest and still the fastest to write. The detail that catches people is that a user crontab has five fields before the command and a system crontab has six - the extra one being the user to run as.
Deploy and Maintain Guide 43 of 67 Beginner
- OSRHEL 10.0 (Coughlan)
- Kernel6.12.0-55.9.1.el10_0
- dnf4.20.0
- Flatpak1.16.0
- TimeAbout 13 min
- Reviewed23 August 2026
Written against the versions above. The package is **cronie** and the service is **crond**. `crontab -e` edits your own; `crontab -e -u <user>` edits somebody else's and needs root. Never edit `/var/spool/cron/<user>` directly - `crontab` validates the syntax and reloads, and a hand-edited file can be silently ignored.
| Server Name | IP Address | OS | Roles | CPU | RAM | HDD |
|---|---|---|---|---|---|---|
| RHCSA-A01 | 192.168.0.31 | RHEL 10.0 (Coughlan) | Practice node (graded) - spare /dev/sda | 2 Core | 4 GB | 50 GB + 15 GB |
Before you start
- A sudo-capable account.
- The session writes a user crontab and a file in
/etc/cron.d, and removes both.
-
The format
-
A user crontab
-
System crontabs, and the sixth field
-
Shorthand, and checking it ran