Linux Administration Handbook, Second Edition

8.6. Exercises

E8.1	A local user on your system has been abusing his crontab privileges by running expensive tasks at regular intervals. After asking him to stop several times, you are forced to revoke his privileges. List the steps needed to delete his current crontab and make sure he can’t add a new one.
E8.2	Think of three tasks (other than those mentioned in the chapter) that might need to be run periodically. Write crontab entries for each task and specify into which crontab files the entries should go.
E8.3	Choose three entries from your system’s crontab files. Decode each one and describe when it runs, what it does, and why you think the entry is needed. (Requires root access.)
E8.4	Write a script that keeps ...