1.11 - Linux Commands Flashcards
1
Q
Linux commands
A
- The command line - Terminal, XTerm, or similar
- Commands are similar in both Linux and macOS
– Mac OS derived from
BSD (Berkeley Software Distribution) Unix
– This section is specific to Linux - Download a Live CD or install a virtual machine
– Many pre-made Linux distributions are available - Use the man command for help - An online manual
> man grep
2
Q
Bash - ls
A
- List directory contents
– Similar to the dir command in Windows - Lists files, directories
– May support color coding;
– Blue is a directory, red is an archive file, etc. - For long output, pipe through more:
> ls -l | more
(use q or Ctrl-c to exit)
3
Q
Bash - pwd
A
- Print Working Directory
– Displays the current working directory path
– Useful when changing directories often
4
Q
Bash - mv
A
- Move a file or rename a file
- mv SOURCE DEST
> mv first.txt second.txt
5
Q
Bash - cp
A
- Copy a file - Duplicate files or directories
- cp SOURCE DEST
> cp first.txt second.txt
6
Q
Bash - rm
A
- Remove files or directories - Deletes the files
- Does not remove directories by default
– Directories must be empty to be removed or
must be removed with -r
7
Q
Bash - chown
A
- Change file owner and group - Modify file settings
- sudo chown [OWNER:GROUP] file
> sudo chown professor script.sh
8
Q
Bash - su / sudo
A
- Some commands require elevated rights
-
sudo
– Execute a command as the super user or user ID
– Only that command executes as the super user -
su
– Become super user or change to a different user
– You continue to be that user until you exit
9
Q
Bash - chmod
A
- Change mode of a file system object
– r=read, w=write, x=execute
– Can also use octal notation
– Set for the file owner (u), the group(g),
others(o), or all(a) - chmod mode FILE
> chmod 744 script.sh - chmod 744 first.txt
– User; read, write, execute
– Group; read only
– Other; read only - chmod a-w first.txt
– All users, no writing to first.txt - chmod u+x script.sh
– The owner of script.sh can execute the file
10
Q
Bash - apt-get
A
- Advanced Packaging Tool
– Handles the management of application packages
– Applications and utilities - Install, update, remove
> sudo apt-get install wireshark
11
Q
Bash - yum
A
- Yellowdog Updater, Modified (yum) -
Install, delete, update - Manages RPM packages
– Red Hat Package Manager - RPM Package Manager
– A Linux distribution will commonly use either
yum or apt-get
12
Q
Bash - ip
A
- Manage the network interfaces
– Enable, disable, configure addresses,
manage routes, ARP cache, etc. -
ip address
– View interface addresses -
ip route
– View the IP routing table -
sudo ip address add 192.168.121.241/24 dev eth0
– Configure the IP address of an interface
13
Q
Bash - df
A
- Disk Free - View file systems and free space
-
df
– View number of blocks -
df -h
– View human-readable sizes
14
Q
Bash - grep
A
- Find text in a file
– Search through many files at a time
grep PATTERN [FILE]
> grep failed auth.log
15
Q
Bash - ps
A
- View the current processes
– And the process ID (PID)
– Similar to the Windows Task Manager - View user processes
ps - View all processes
ps -e | more
