Linux Command

File Commands

ls                     -list directory
ls -al                   -formatted listing with hidden files
ls -ltr                  -formatted listing ordered by time
cd dir                   -change to directory
cd -                     -go to directory in previously
cd                       -go to home directory
pwd                      -show current directory path
mkdir dir                -make 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/move file1 to file2 if file2 is an existing dir, moves file1
ln -s file link          -create symbolic link link to file
touch file               -create or update file
cat > file               -places standard input into file
more file                -output the contents of file
head file                -output the first 10 lines of file
tail file                -output the last 10 lines of file
tail -f file             -output the contents of file as it grows, starting with the last 10


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



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

 Save File in Vi / Vim Text Editor

Command    Description
q    :Quit
q!    :Quit without saving changes i.e. discard changes
r      : :fileName    Read data from file called fileName
wq     :Write and quit (save and exit)
w    :fileName    Write to file called fileName (save as)
w!   :fileName    Overwrite to file called fileName (save as forcefully)