How to change mac address in ubuntu linux

1. Enter command in terminal to find interface name

      ifconfig

    e.g. my interface name is wlp3s0

2. then Enter command in terminal

   sudo ip link set dev interface_name address new_mac_adresss


e.g.    sudo ip link set dev wlp3s0 address 48:87:ca:97:b9:e2 

My new mac is now 48:87:ca:97:b9:e2

again check with ifconfig command succesfully changed your mac address 
warning:--   Please turn off your wifi when sudo ip link set dev wlp3s0 address 48:87:ca:97:b9:e2 run in terminal after sucesfully executing comad turn on wi-fi 







 Download Python script MAC changer

 

Enable telnet service in ubuntu linux 18.04

1.run command in terminal

sudo apt-get install xinetd telnetd 

2.edit  /etc/inetd.conf file from this commad

sudo nano  /etc/inetd.conf

3.add these lines and save 

telnet stream tcp nowait telnetd /usr/sbin/tcpd /usr/sbin/in.telnetd

4.Edit /etc/xinetd.conf,make its content look like following:

    delete defaults section of code and add this 

service telnet
{
disable = no
flags = REUSE
socket_type = stream
wait = no
user = root
server = /usr/sbin/in.telnetd
log_on_failure += USERID
} 

5.Use this command to start telnet server:

sudo /etc/init.d/xinetd restart     

your service has started  

Move close minimize maxmize button on left side or right side in linux ubuntu

Run command in terminal

gsettings set org.gnome.desktop.wm.preferences button-layout ':close,maximize,minimize'

To revert back your setting  run again

gsettings set org.gnome.desktop.wm.preferences button-layout ':close,maximize,minimize' 

To revert back your setting  run again 

How to create shortcut in linux and ubuntu

run in terminal
ln -s source-path destination-path
example-
my file name name.mp4 in downloads folder and i want to create shortcut on desktop and my pc name rizwan
ln -s /home/rizwan/downloads/name.mp4  /home/rizwan/Desktop/

Linux basic command

1. pwd              show current directory
2. ls                   show all files in current directory
3. cd path         change directory to path
4. cd ..              back directory
5. mkdir newfoldername               create new folder
6. rmdir foldername                      delete folder
7. touch newfilename                     create new file
8.  man & --help                          show manual & hint
9. cp source-path-or-file  destination        copy files or directory 
10. mv source-path-or-file  destination        move file or directory
11. df                                                      show disk usage