Deploy, configure, and maintain systems

Question 1

cron order

Answer 1

# For details see man 4 crontabs
# Example of job definition:
# .---------------- minute (0 - 59)
# |  .------------- hour (0 - 23)
# |  |  .---------- day of month (1 - 31)
# |  |  |  .------- month (1 - 12) OR jan,feb,mar,apr ...
# |  |  |  |  .---- day of week (0 - 6) (Sunday=0 or 7) OR sun,mon,tue ...
# |  |  |  |  |
# *  *  *  *  * user-name  command to be executed

Question 2

how to start a service

Answer 2

systemctl start httpd

Question 3

how to stop a service

Answer 3

systemctl stop httpd

Question 4

how to make a service start automatically on startup

Answer 4

systemctl enable httpd

Question 5

how to configure the system to boot into a specific target automatically

Answer 5

systemctl set-default multi-user.target

Question 6

how to see all time zones

Answer 6

timedatectl list-timezones

Question 7

how to set time zone to specific zone

Answer 7

timedatectl set-timezone America/Chicago

Question 8

how to set time to specific time

Answer 8

timedatectl set-time 9:00:00

Question 9

how to set ntp

Answer 9

timedatectl set-ntp true

need to double check what this actually does

Question 10

how to see the sources for chrony

Answer 10

chronyc sources -v

Question 11

how to install a software package

Answer 11

yum install package

Question 12

how to search for a software package

Answer 12

yum search package

Question 13

how to delete a software package

Answer 13

yum remove package

Question 14

how to add a yum repository source

Answer 14

yum config-manager –add-repo=”https://dl.fedoraproject.org/pub/epel/8/Everything/x86_64/”

Question 15

how to enable a disabled yum repository

Answer 15

yum config-manager –enable rhel-8-server-debug-rpms

Question 16

how to view all yum repositories

Answer 16

yum repolist all

Question 17

how to install a software package that is not signed

Answer 17

yum install –nogpgcheck package

Question 18

how to update all packages on the system

Answer 18

yum update

Question 19

how to update just packages that have security issues

Answer 19

yum update –security

Question 20

how to view a list of all packages installed on the system

Answer 20

yum list installed

Question 21

how to view all the past successful yum runs

Answer 21

yum history

Question 22

how to revert a yum run

Answer 22

yum history undo 100

100 is the number of the run you want to undo, this can be found by running yum history

Question 23

how to install a module

Answer 23

yum module install package

Question 24

how to remove a module

Answer 24

yum module remove package

Question 25

how to disable a module

Answer 25

yum module disable package

Question 26

how to search for available modules

Answer 26

yum module search package

Question 27

configure the system to use /run/tempFiles to store temporary files that can be easily cleaned up if not accessed within 30 seconds by the command systemd-tempfiles –clean with permissions of 0700.

Answer 27

vim /etc/tmpfiles.d/tempFiles.conf
d /run/tempFiles 0700 root root 30s
systemd-tmpfiles –create /etc/tmpfiles.d/tempFiles.conf

Question 28

how to change NTP server to classroom.example.com

Answer 28

vim /etc/chrony.conf

server classroom.example.com iburst