joakimteixeira/linux-cheat-sheet

Cheat-sheet with my most frequent Linux commands

Cheat Sheet - #Linux

My most used Linux commands

Indice

• Subtitle
• Subtitle Example
• File Editing
• Wildcard Example
• File info
• File / Folder Creation
• Command Info
• SSH Key for Remote Access
• Network Troubleshooting
• Process Management

Subtitle

Input	Description
[ ]	Brackets only represent a user input (what you have to type)
[file]	Type a file name + extension (".txt", ".css", ".js", etc)
[folder]	Type a folder name
[directory]	Type a directory path
[word]	Type a Word
[host]	Type a remote computer name + IP address (example: [email protected])
[PID]	Type a process ID. It's a number listed in "top" or "ps" command and identifies the process
[site]	Type a site name or IP address

Subtitle Example

• Command description: touch [file]
• Desired input #1: touch myFile.html
• Desired input #2: touch hello.txt

Below, the commands are organized in groups:

File Editing

Command	Description
nano [file]	Open file to edit
mv [file] [file / directory]	Rename/move file
cp [file] [directory]	Copy to directory
rm -rf [file]	Remove file (r = recursive, f = force)
rm *[file]	Wildcard: remove all files with same letter combination or extension

Wildcard Example

rm *[file]	Description
rm *	Remove all files
rm *.js	Remove all javascript files
rm a*.txt	Remove all text files beginning with the letter "a"

File info

Command	Description
list -l	List files with detailed info (l = long)
list -a	List visible & insisible files (a = all)
cat [file]	Concatenate: print file content
head [file]	Print file's first 10 lines
tail [file]	Print file's last 10 lines
less [file]	Print file with navigation
grep [word] [file]	Search word in file and print corresponding line
find -name [file]	Find file directory

File / Folder Creation

Command	Description
touch [file]	Create file
mkdir [folder]	Create folder
echo [word] > [file]	Write word inside file

Command Info

Command	Description
man [command]	Get documentation about command
history [command]	Get the list of all typed commands
CTRL + R [command]	Reverse i-search: find command from history, based on typed input
cd ~/.bash_history	Go to invisible file in the HOME directory, which contains command history log

SSH Key for Remote Access

Command	Description
ssh-keygen	Create SSH key pair
ls .ssh	Confirm if SSH key was created
ssh-copy-id [host]	Copy SSH key to remote computer
ssh [host]	Login remote computer with SSH

Network Troubleshooting

Command	Description
ifconfig	Get network info
hostname -I	Get IPV4 & IPV6 info
route	Check if "default" line has IP, and if so, you can contact servers outside the local network
ping [site]	Check "packet loss" summary to see if you have a good internet connection
whois [site]	Get all info about domain names registered on the Internet
whois [site] | grep [word]	Search for word inside "whois" command (| = group commands together)
whois [site] | head	Get first 10 lines of "whois" command

Process Management

Command	Description
top	List processes executing in the computer
ps	Similar to "ls" command, but for processes
ps aux	More detailed info to "ps" command
kill [PID]	Kill process