107.2 Automate System Administration Tasks By Scheduling Jobs

Question 1

Alias for batch command.

Answer 1

at -b

Question 2

cats the details of the job to standard output.

Answer 2

at -c [job ID]

Question 3

Two commands to list pending jobs.

Answer 3

at -l

atq

Question 4

at argument to never send mail to user.

Answer 4

at -M

Question 5

Command to execute job at specified time.

Answer 5

at -t [time]

Question 6

Command to show when a batch job will run.

Answer 6

at -v

Question 7

The daemon that runs jobs queued by at.

Answer 7

atd

Question 8

Command to set time to wait between batch jobs.

Answer 8

atd -b

Question 9

Command to process at/batch queue only once.

Answer 9

atd -s

Question 10

Type of job that executes when the specified load level permits.

Answer 10

batch

Question 11

Command to delete cron job number 7.

Answer 11

atrm 7

Question 12

Type of jobs that can run simultaneously with complex scheduling.

Answer 12

at jobs

Question 13

Type of jobs that run sequentially when system load is low.

Answer 13

batch jobs

Question 14

How to restrict cron jobs from sending an email to the user?

Answer 14

Append >/dev/null 2>&1 to the end of the crontab entry

Question 15

What must be at the end of each crontab entry?

Answer 15

A newline character

Question 16

Command for users to edit their crontab file.

Answer 16

crontab

Question 17

Command to remove the user’s crontab file.

Answer 17

crontab -r

Question 18

crontab file format:

Answer 18

minute, hour, day of month, month of year, day of week, username, and command

Question 19

In crontab, what happens if both day of month and day of week are specified?

Answer 19

This creates an or condition, both will be executed.

Question 20

Commands that are best suited for running a command once.

Answer 20

at

batch

Question 21

Command best suited for running a command on a repeating interval.

Answer 21

crontab

Question 22

Command used to execute cron jobs periodically, with a frequency specified in days and a wait time in minutes, and will run jobs if missed?

Answer 22

anacron

Question 23

Path to the system cron table

Answer 23

/etc/crontab

Question 24

Path to files that specify which users are allowed and not allowed to run cron jobs

Answer 24

/etc/cron.allow and /etc/cron.deny

Default is a blank cron.allow to allow all users to run cron jobs.

Question 25

Path to files that specify users who are allowed or not allowed to run batch jobs.

Answer 25

/etc/at.allow and /etc/at.deny

If at.allow exists, only those users specified can use at.

Question 26

Path to centralized location to manage crontabs named by username on servers with many users.

Answer 26

/etc/cron.d/

Question 27

Path where individual user crontabs are stored.

Answer 27

/var/spool/cron/*

Question 28

Path where anacrontab stores job identifiers like cron.daily, cron.weekly, and cron.monthly.

Answer 28

/var/spool/anacron/*

Question 29

Path to the cron daemon.

Answer 29

/usr/sbin/crond

Question 30

Path to the shell used to execute cron jobs.

Answer 30

/usr/bin/sh

Question 31

Method for editing anacrontab.

Answer 31

vi /etc/anacrontab

Question 32

If an empty /etc/cron.deny exists and no /etc/cron.allow exists, can users still use the crontab command?

Answer 32

Yes