Chapter 7

Question 1

groups

Answer 1

means of organizing users. groups parallel users

345

Question 2

GIDs

Answer 2

group IDs

number created to track groups

346

Question 3

UIDs

Answer 3

User IDs

number created to track users

346

Question 4

useradd parameter

-c

Answer 4

comment parameter passes the comment field for the user. may include contact info for the administrator

348

Question 5

useradd parameter

-d or home-dir

Answer 5

used to specify a user’s account home directory

348

Question 6

useradd parameter

-e expire-date

Answer 6

used to specify when an account will be disabled as expressed in YYYY-MM-DD format

348

Question 7

useradd parameter

-f inactive-days

Answer 7

specifies the number of inactive days are acceptable before the password expires

348

Question 8

useradd parameter

-g default-group

Answer 8

used to set the name or GID

348

Question 9

useradd parameter

-G group[,…]

Answer 9

sets the names or GIDs of one or more groups to which the user belongs

349

Question 10

useradd:

/etc/login.defs file

Answer 10

specifies whether or not to create a user’s home directory when the account is created via the CREATE_HOME setting

349

Question 11

useradd parameter

-M

Answer 11

forces the system not to create a home directory, even if /etc/login.defs specifies that this action is the default

349

Question 12

useradd parameter

-p password

Answer 12

passes the pre-hashed password for the user to the system.

349

Question 13

useradd parameter

-s shell

Answer 13

sets the name of the user’s default login shell

defaults to /bin/bash

349

Question 14

useradd parameter

-u UID

Answer 14

creates an account with the specified user ID value (UID). This must be a counting number

349

Question 15

useradd parameter

-r

Answer 15

specifies the creation of a system account

350

Question 16

useradd parameter

-N

Answer 16

This disables:
In Red Hat and similar distros, the system creates a group with the same name as the specified username.

350

Question 17

passwd parameter

-k

Answer 17

indicates that the system should update an expired account

351

Question 18

passwd parameter

-l

Answer 18

locks an account by prefixing the hashed password with an exclamation mark. The account can not be logged in, but the files are safe.

351

Question 19

passwd parameter

-u

Answer 19

unlocks an account by removing the exclamation mark.

351

Question 20

passwd parameter

-d

Answer 20

removes the password from an account rendering it passwordless.No warning messages.

351

Question 21

passwd parameter

-S

Answer 21

displays information about the password for an account. Info displayed includes what kind of algorithm was used to hash the password

351

Question 22

usermod

Answer 22

changes an existing account instead of creating a new one

352

Question 23

chage command

Answer 23

allows you to modify account settings relating to account expire if either of two conditions are true

The password hasn’t been changed in a specified time period

The system date is past a predetermined time

354

Question 24

chage parameter

-l

Answer 24

option causes chage to display accoount expiration and password aging information for a particular user

354

Question 25

chage parameter -m mindays

Answer 25

sets the minimum number of days between password changes. 0 indicates that a user can change a password multiple times in a day 354

Question 26

chage parameter -M maxdays

Answer 26

sets the maximum number of days that may pass without changing the password 354

Question 27

chage parameter -d lastday

Answer 27

sets the last day a password was changed. Linux normally maintains this value automatically 354

Question 28

chage parameter -I inactivedays

Answer 28

sets the number of days between password expiration and disablement 354

Question 29

chage parameter -E expiredate

Answer 29

sets an absolute expiration date on a password 354

Question 30

chage parameter -W warndays

Answer 30

sets the number of days before account expiration that the system will send impending expiration warnings to the user 354

Question 31

journalctl

Answer 31

shows you all of the systemd-journald collected data 376

Question 32

NTP

Answer 32

Network Time protocol most common protocol for setting the time in linux. one of the most popular, flexible, and accurate network time tools. 380

Question 33

pool.ntp.org

Answer 33

subdomain dedicated to servers that have volunteered to function as public NTP servers 384

Question 34

What cannot be running when you issue the ntpd -gp command because if it is, you will get no warning message or error message, just a prompt back with no synchronization completed?

Answer 34

NTP daemon 386

Question 35

Function of groups in Linux

Answer 35

Linux groups enable security features to be applied to arbitrary groups of users. Each group holds an arbitrary collection of users, and group permissions can be set on files, giving all group members the same access rights to the files 389