Basic Linux Commands

Ø File Handling Linux Commands

# man command (show all information about this command) 

# pwd  -- show current working directory

# cd     -- change current directory

# ls      -- list files or directory

# ls -a -- show hidden file or directory

# ls -lrt   -- show directory/file with ownership

# ls -al (show all directory include hidden directory with property like size, ownership etc.)

# mkdir test   -- create a directory name is test

# rm -rf test   -- remove test directory

# rm f1  -- remove f1 

# rm -rf d1 -- remove directory

# mv file1 file2 -- rename file1 to file2

# mv test.txt /root/test/  -- move test.txt file to /root/test directory

# cp source destination --copy source to destination directory

# less file --show file content 

# cat > hello.txt (Create file and input from keybord)

# history --show recently used command

  

Ø Check the Linux Version, Release name & Kernel version

# uname -a (Print all Information)

# uname -r (Print the kernel name)

# cat /p

# roc/version

# cat /etc/issue

# cat /etc/redhat-release

# lsb_release –a

# tail /etc/redhat-release

Ø Check Swap Space

# swapon –summary (summary of swap space)

# cat /proc/swaps (swap usage information)

# free -h (display use and free swap space in gigabyte)

# top (use to check swap space)

  

Ø Linux System Administrator

   

# uptime 

# uptime -v 

# w 

# users 

# who 

# who -b 

# who -r 

# who -a 

#  crontab -l 

# service httpd start(execute the script)

# top 

# last 

# ps -ef | grep init (show init process only)

# kill- 9 7508(Process ID) (kill command to terminate process)

# reboot (restart the system)

# init 6 (restart the system)

Ø File System

# cat output.log | less or more (view file)

# whoami 

# locate text.txt 

# sort file.txt

# sort -r file.txt 

# vi /etc/test.txt (text editor)

# free 

# free -h 

# grep test /etc/passwd (grep search for a given string in a file)

# grep -i serachstring /etc/passwd (grep search for a given string in a file)

# find / -name test (used to search files, strings and directories)

# lsof -u erpdev (List of all open files by user erpdev)

Ø Archival

# tar -cvf archive-name.tar /home (tar command is used to compress files and folders)

# tar -xvf archive-name.tar (extract tar archive file)

# zip original.zip original (zip original file)

# unzip original.zip ( unzip original.zip file)

Ø Network

# ssh -v (check the version of ssh user)

# ssh remote_host (you connect to a remote host)

# scp (Copy files securely and remotely over servers)

# ftp 192.168.50.2 (used to connect to remote ftp host)

# sftp 192.168.50.2 (sftp is secure file transfer protocol)

# ftp > mput *.txt (Putting multiple files in remote host)

# ftp > mget *.txt (mget to download multiple files from remote host)