Introduction to Linux II
Introduction to Linux II Chapter 8 Exam Answer 2016
1. The daemon associated with the cron utility is called the ___________ daemon.
- cdaemon
- crondaemon
- crond
- cron
2. The crontab command can be used to:
- Create crontab files
- Remove crontab files
- List crontab files
- All choices are valid
3. System crontabs are generally found in which of the following directories?
- /root; /etc
- /var/spool/cron; /etc/cron.d
- /etc; /bin
- /var/spool/cron.d; /etc/cron
4. All commands that are run from system crontabs require root privileges.. True or False?
- True
- False
5. Commands specified in a crontab file will run only if the root user is logged in.. True or False?
- True
- False
6. In the time fields of a crontab file entry, a _________is used to denote a range of values.
- ( )
- [ ]
- –
- /
7. The crontab keyword @reboot implies that the job runs:
- Once, at startup
- Once a day
- Every time a user logs in
- Each time the crond daemon starts
8. The system administrator wants to create a crontab entry to perform daily backups. Which of the following keywords should be used?
- @today
- @daily
- @backup
- Cannot be done
9. The system administrator wants to check the status of a database every hour. Which of the following crontab entries will ensure that the script runs every hour (on the hour) from 8AM to 5PM, Monday through Friday?
- 00 08-17 * * 1-5 /home/appuser/bin/check-db-status
- 00 08-05 * * 1-5 /home/appuser/bin/check-db-status
- 00 08-17 * * 00 /home/appuser/bin/check-db-status
- 00 08-17 * * 5 /home/appuser/bin/check-db-status
10. Which of the following commands can be used to view the current contents of a crontab file?
- crontab –l
- crontab –p
- crontab –r
- crontab –v
11. Which of the following commands can be used to remove all the crontab entries?
- crontab –r
- crontab –v
- crontab –l
- crontab –p
12. Refer to following cron job entry:. 0 9-18 * * * /home/joe/bin/check-db-status. The job…
- Executes check-db-status on all days between 9 AM and 6 PM
- Executes check-db-status Monday to Friday between 9 AM and 6 PM
- Executes check-db-status at every hour on all days
- Executes check-db-status at every hour on Monday to Friday
13. How would you schedule a cron job to run every second?
- By using the keyphrase @second
- Create 60 jobs which run every minute
- Using a cron job, it is not possible to schedule a job which runs every second
- By putting an entry similar to * * * * * <job>
14. A Linux server, configured for the UTC time zone, is accessed by users from other time zones. The cron jobs scheduled on the server will run:
- As per the time zone of location where the server is kept
- As per the time zone of respective users
- As per UTC time zone
- As per the TZ environment variable setting in the crontab file
15. The crond daemon can be restarted using the command /etc/init.d/crond restart
- False
- True
16. The system administrator wants to allow certain users to access the crontab command but not others. This can be done by:
- Add account name(s) to have access in the system crontab file
- Selective access is not possible
- Granting them root privileges
- Managing entries in cron.allow and cron.deny files
17. A Linux system has entries in both the cron.allow and cron.deny files. Which users, other than root, will have access to the crontab command?
- Users specified in cron.allow have access to crontab; cron.deny will be ignored
- Only root will have access to crontab
- All users except those specified in the cron.deny file will have access to crontab
- Users specified in cron.allow but not included in cron.deny will have access to crontab
18. Only 5 out of 100 Linux users in ABCajun Corp need access to crontab. The administrator should:
- Create cron.deny and add all the users in the file
- Create cron.allow and add those five users to the file
- Create cron.deny and add those five users in the file
- Create both cron.allow and cron.deny files. Add five users in cron.allow and remaining ninety five in cron.deny
19. A Linux server may not be powered-on all the time. Which of the following options is most suitable to run scheduled jobs on this server?
- anacron
- cron
- cron.allow
- cron jobs with only daily jobs
20. What does the delay field in an anacrontab entry signify?
- The command should wait for a specified number of minutes after running the previous command
- The command should delay the processing by a specified number of minutes
- The command should wait for a specified number of seconds after the machine starts
- The command should wait for a specified number of minutes after the machine starts
21. To force a job to be run irrespective of its timestamp, the anacron command can be used with which of the following options?
- –n
- –f
- –s
- –u
22. The cron scheduler should be used if the jobs are to be run at a particular hour and minute.. True or False?
- True
- False
23. A one-time job needs to be scheduled for a specific time. Which of the following commands is most suitable for the task?
- at
- anacron
- cron
- batch
24. Pam wants to schedule a one-time task using the at command and receive an email once it is complete. Which of the following at command options should she use?
- –m
- –f
- –v
- –x
25. After executing the atq command, the following jobs are displayed:
2 2014-11-22 22:00 a test_user
3 2014-11-22 20:00 a root
4 2014-11-22 22:45 a oracle_dba
Which of the following commands will delete job #2?
- atrm test_user
- test_user should manually delete the entry
- atrm 2
- at -r 2
26. The at.allow and at.deny files can be used to control access to:
- at and batch commands
- anacron
- at command only
- All programs used for scheduling
27. Rob has to schedule a job to accomplish a one-time task. He wants to run the job during off-peak hours only. Which of the following is most suitable to schedule this task?
- cron
- at
- batch
- anacron
28. batch commands are executed only when the system’s load average drops below which of the following by default?
- 1.0
- 0.5
- 0.8
- 0.2
29. The default value for load average for running the batch command can be changed using which of the following commands?
- atd –o
- atd –l
- atd –n
- It cannot be changed
