Linux Cheat Sheet

File Commands

• ls – directory listing 
• ls -al – formatted listing with hidden files 
• cd dir - change directory to dir 
• cd – change to home 
• pwd – show current directory 
• mkdir dir – create a directory dir 
• rm file – delete file 
• rm -r dir – delete directory dir 
• rm -f file – force remove file 
• rm -rf dir – force remove directory dir * 
• cp file1 file2 – copy file1 to file2 
• cp -r dir1 dir2 – copy dir1 to dir2; create dir2 if it doesn't exist 
• mv file1 file2 – rename or move file1 to file2 if file2 is an existing directory, moves file1 into directory file2

Process Management

• ps – display your currently active processes 
• top – display all running processes 
• kill pid – kill process id pid 
• killall proc – kill all processes named proc * 
• bg – lists stopped or background jobs; resume a stopped job in the background 
• fg – brings the most recent job to foreground 
• fg n – brings job n to the foreground 

SSH

• ssh user@host – connect to host as user 
• ssh -p port user@host – connect to host on port port as user 
• ssh-copy-id user@host – add your key to host for user to enable a keyed or passwordless login 

Searching 

• grep pattern files – search for pattern in files 
• grep -r pattern dir – search recursively for pattern in dir 
• command | grep pattern – search for pattern in the output of command 
• locate file – find all instances of file

Network

• ping host – ping host and output results 
• whois domain – get whois information for domain 
• dig domain – get DNS information for domain 
• dig -x host – reverse lookup host 
• wget file – download file 
• wget -c file – continue a stopped download