Some commands for Ubuntu 14.10 Utopic Unicorn

Change hostname / Computer name

Temporary:-

hostname [NewComputerNameHere]

The command above will last until restart.

Permanently:-

sudo gedit /etc/hostname /etc/hosts

The command above will let you edit two files, /etc/hostname and /etc/hosts

1. For the /etc/hostname file can be easily done.
    Just rename the existing name to the new computer name you want.
    Then make sure you save your file.

2. For the /etc/hosts file, you have to look for the following line in the file.
    127.0.1.1 YOUR-HOSTNAME

    Replace your new computer name with the old name.
    Then make sure you save your file.
    Finally, reboot your system to let it take effect.

Check your network IP address

hostname -I

The command above will show all addresses for the host.

ifconfig

The command above will show quite an amount of information. For this section, we are interested in the network IP address, therefore, we will lookout for the keyword "inet addr". Beside this will be the IP address for this network interface. 

You might had notice that there are multiple inet addr on your terminal. 

One under wlan0, one under eth0 or one under lo.

1. wlan0 will normally be the first wireless network card that your system have.

2. eth0 will normally be the first wired network port that your system have.

3. lo is a loopback interface on your system that is normally use for testing and troubleshooting for

    software developers.

Check which account you are currently using

whoami

The command above will show which user are you currently. This command is useful when you switch users frequently using the su command and you had lost track of which account are you in currently.

Sending Ctrl + Alt + Del to Remote Client in Remote Desktop Connection Session

If you press Ctrl + Alt + Del while using Remote Desktop Connection, your local PC will response to the key pressed rather then the remote PC.

In order to send Ctrl-Alt-Del keystrokes to remote computer connected via Remote Desktop Client, just press Ctrl + Alt + End.

Linux: CentOS 6.3 - Guide to install GNOME Desktop from CLI using yum

1. You would need to install "X Windows System" first, as this is the based that provide GUI and rich input device capability before installing GNOME Desktop. This will take a while as yum would download packages from the net before installing, therefore please have your internet connection setup before executing. Command to execute :-

# yum groupinstall -y 'X Window System'

2. Next will be the command for installing GNOME Desktop Environment :-

#  yum groupinstall -y 'Desktop'

3.  Done. To start GNOME type the following command :-

# startx

Note: If you would like to start GNOME automatically after reboot, you would need to edit the /etc/inittab file by changing the line " id:3:initdefault: " to " id:5:initdefault: " in the file.

How to Determine Which Domain Controller a PC is Using from Command Prompt (cmd)?

1. Type in that window "set logonserver" without quotes. Press "Enter" key.
2. Read the result of the output. The output will show you LOGONSERVER= and after the equals sign will be the name of the logon server.