Chapter 12

Question 1

Linux is a blank, meaning that it provides features to help multiple individuals use the computer.

Answer 1

multiuser OS

Question 2

Blanks enable multiple users to share the same computer without causing one another too much trouble

Answer 2

Accounts

Question 3

Most account features are defined in the blank file, which consists of colon-delimited lines, with each line defining a single account.

Answer 3

/etc/password

Question 4

The blank field in the /etc/password record is the most relevant feature that usually consists of lowercase letters and numbers. It’s the first field.

Answer 4

username

Question 5

The blank field in the /etc/password record is the code that is required at login, and is the second field.

Answer 5

password

Question 6

The blank field in the /etc/password record is a number that tracks accounts and is the third field in a record (usually greater than 1000 for regular users)

Answer 6

user identification number (UID)

Question 7

The blank field in the /etc/password record tracks account to one or more collection of accounts with predefined permissions. It’s the fourth field in a record.

Answer 7

group identification number (GID)

Question 8

The blank field in the /etc/password record normally hods the user’s full name, although it can hold other information, and it comes after the GID.

Answer 8

Comment

Question 9

The blank field in the /etc/password record is a file directory listing for an account’s home base. It comes as the 6th field in the record.

Answer 9

Home directory

Question 10

The blank field in the /etc/password record is associated with every account and is normally Bash.

Answer 10

Default shell

Question 11

True or False: The password field in most modern /etc/password files is salted and hashed since the file is available to all users.

Answer 11

False

Question 12

Where is the salted and hashed password actually stored?

Answer 12

the /etc/shadow file

Question 13

Name the first field in the record of the /etc/shadow file.

Answer 13

Username

Question 14

Name the second field in the record of the /etc/shadow file.

Answer 14

password

Question 15

Name the third field in the record of the /etc/shadow file.

Answer 15

Last password change

Question 16

In the /etc/shadow file, how is the last password change displayed?

Answer 16

As the number of days since Jan 1, 1970

Question 17

Name the fourth field in the record of the /etc/shadow file.

Answer 17

Days until a change is allowed

Question 18

Name the fifth field in the record of the /etc/shadow file.

Answer 18

days before a change is required

Question 19

Name the sixth field in the record of the /etc/shadow file.

Answer 19

Days of warning before password expiration

Question 20

Name the seventh field in the record of the /etc/shadow file.

Answer 20

Days between expiration and deacitvation

Question 21

Name the eighth field in the record of the /etc/shadow file.

Answer 21

Expiration date

Question 22

in the /etc/shadow file, how is the expiration date for the account displayed.

Answer 22

number of days since Jan 1, 1970

Question 23

Name the ninth field in the record of the /etc/shadow file that is normally blank

Answer 23

Special flag

Question 24

The blank file is used to define groups

Answer 24

/etc/group

Question 25

Name the first field in the record of the /etc/group file.

Answer 25

group name

Question 26

Name the second field in the record of the /etc/group file.

Answer 26

password

Question 27

Name the third field in the record of the /etc/group file.

Answer 27

GID

Question 28

Name the fourth field in the record of the /etc/group file.

Answer 28

User list

Question 29

If you want to create that are associated with another group to which you belong (other than your primary group) use the blank command

Answer 29

newgrp

Question 30

What command displays your current user ID?

Answer 30

whoami

Question 31

If you need more information about your user ID, what command would you use?

Answer 31

id

Question 32

The id utility shows what three areas of identification?

Answer 32

1) Your userID and userName 2) Your current groups with GID 3) All your group memberships

Question 33

Name the option(s) for id that displays the effective group id

Answer 33

--group -g

Question 34

Name the option(s) for id that displays all groups to which you belong

Answer 34

--groups -G

Question 35

Name the option(s) for id that displays only the user data

Answer 35

--user -u

Question 36

Name the option(s) for id that when used in conjunction with -g, -G or -u lists only the name and not the ids

Answer 36

--name -n

Question 37

Name the option(s) for id that when used in conjunction with -g, -G or -u lists only the ids and not the name

Answer 37

--real -r

Question 38

To learn who is online, use the blank command

Answer 38

who

Question 39

When using the who command what fields are returned for each record?

Answer 39

Username, Terminal identifier, Login date and time, Remote host

Question 40

Which command with who provides as a summary the total number of users online

Answer 40

--count or -q

Question 41

What command is similar to whoami but displays more information

Answer 41

who am i

Question 42

As an alternative to who, the blank command provides even more verbose results

Answer 42

w

Question 43

In addition to the fields found in the results of a who command, what additional fields are added in w?

Answer 43

session's idle time JCPU (total amount of CPU time for session) PCPU (total amount of CPU time for current process) What column (program they are running)

Question 44

The blank user account has superuser privilege to manage the features of the computer as a whole

Answer 44

root

Question 45

Activities like browsing the web, writing letters, managing a music collection are known as blank

Answer 45

user tasks

Question 46

The root user exists to complete blank tasks like installing software, preparing a new disk, and managing ordinary user accounts

Answer 46

administrative tasks

Question 47

The root account has the ability to blank and blank every file on the computer

Answer 47

read write

Question 48

Name three ways you can acquire root privileges

Answer 48

login as root use su use sudo

Question 49

The blank command allows you to change your identity within a shell

Answer 49

su

Question 50

If you type su without a username after the command, you are switched to what account?

Answer 50

root

Question 51

When your are done with commands after using su, what do you type to relinquish the root user?

Answer 51

exit

Question 52

If you use a blank with the su command or a blank with a blank, you will switch users and open a login session that runs the target user's login scripts, which usually sets up their environment variables

Answer 52

- - username

Question 53

The blank command is similar to su, but it only allows you to run one command at a time

Answer 53

sudo

Question 54

Of the ways to get root user privileges, only the blank command tracks and logs a user's activity to prevent a repudiation environment

Answer 54

sudo

Question 55

What two changes in the shell prompt let you know that you are using the root account

Answer 55

username is changed to root the last character of the prompt is # instead of $

Question 56

What is the purpose of the system account with a UID of 0?

Answer 56

It's the system administrator's account

Question 57

What type of information will you find in the /etc/password for ordinary account users? (select all that apply) A. A UID number b. A complete listing of every group the user belongs C. The path to the user accounts home directory D. The path to the user account's default GUI environment E. The path to the user account's default text-mode shell

Answer 57

A, C, E

Question 58

You want to run the cat /etc/shadow command as root, but you aren't logged in. Which of the following commands will get the job done? A. sudo cat /etc/shadow B. root cat /etc/shadow C. passwd cat /etc/shadow D. su cat /etc/shadow E. admin cat /etc/shadow

Answer 58

A

Question 59

True or False: whoami provides more information than id

Answer 59

False

Question 60

True or False: Linux stores information on its groups in the /etc/groups file

Answer 60

False

Question 61

True or False: As a general rule, you should provide extra care when running programs as root

Answer 61

True

Question 62

The file that associates usernames with UID numbers in Linux is blank

Answer 62

/etc/passwd

Question 63

To learn who is currently logged into the computer and what programs they are running, you can type blank

Answer 63

w

Question 64

UID above 0 and below 500 or 1000 are reserved for use by blank accounts

Answer 64

system

Question 65

A blank environment means that a person cannot deny actions, and the sudo command helps establish this environment

Answer 65

nonrepudiation