Linux commands

Question 1

What command is used to number lines in terminal output?

Answer 1

nl (number lines)

Question 2

What command lets you rename files?

Answer 2

mv (move)

Question 3

What command lets you delete files?

Answer 3

rm (remove)

Question 4

What command lets you view file/directory permissions?

Answer 4

ls -l or ll

Question 5

What character lets you run multiple commands on one line?

Answer 5

; semicolon

Question 6

How do you feed the output of one command as the input of another?

Answer 6

use the pipe | symbol.

Question 7

What command is used to search through directories?

Answer 7

find

Question 8

How to search through all directories recursively?

Answer 8

find / -name. This starts at root.

Question 9

what command lets you change passwords?

Answer 9

passwd {user}

Question 10

What command lets you organize the terminal output?

Answer 10

sort

Question 11

What characters let you funnel a commands output into a recording file?

Answer 11

> ,&raquo_space;, 2>, 2», &>, &»

Question 12

What is the command for finding regular expressions?

Answer 12

grep

Question 13

What are some useful options for grep and what do they do?

Answer 13

-i : ignores case
-v : outputs lines without the regex.
-n : numbers the lines
-l
-o : print only the matching part of a line
-r : searches directories recursively.

Question 14

top

Question 15

ps

Answer 15

Lists all processes currently running.

Question 16

What are some of the options for ps and what do they do?

Answer 16

c:
A:
l:
…

Question 17

What are some of the network utilities in Linux?

Answer 17

ifconfig
route
ping
traceroute
dig
netstat
ssh

Question 18

dig

Answer 18

displays results from DNS serversn

Question 19

netstat

Answer 19

display network statistics …

Question 20

ssh

Answer 20

allows a user to login to a remote machine.

Question 21

traceroute

Answer 21

Displays the routed network path between a client and its destination

Question 22

ifconfig

Answer 22

Display interface config information

Question 23

ping

Question 24

change

Answer 24

Used to change password aging settings for a user

Question 25

date

Answer 25

displays current date and time

Question 26

cal/ncal

Answer 26

displays the current calendar with numerous options.w

Question 27

who

Answer 27

Gives information about users. Related commands are whoami and who am I.

Question 28

what are the permissions symbols?

Answer 28

r: read
w: write
x: execute

Question 29

What methods can be used to change permissions?

Answer 29

The command to change permissions is chmod. You can change it using permissions symbols by using the desired viewer’s symbol (u, g, o, a), an operator, then the permissions symbols you want to add or remove (ex. go+rw). It can also be done numerically with numbers 1-7. Think of rwx as binary, with x in the 1 space, w in 2, and r in 4.