How to broadcast a Message through Terminal to Login users In Fedora, Centos, RedHat, Ubuntu

Do you want to sent message to all logged in users in your system (This works great when you are a System Administrator and many users are logged into same System)?

If you are Running Any Linux Distribution like Fedora, Centos, RedHat, Ubuntu you can send or broadcast message to all user logged in using "WALL" command. To use it on the command line / Terminal.

METHOD 1
========

[root@localhost ~]# wall "Your message Goes here"

Now all users can see the Message Broadcasted by You

[ashwin@localhost tmp]$
Broadcast message from root (pts/2) (Mon Feb 22 12:10:35 2010):

Your message Goes here

METHOD 2
========
[shankar@localhost ~]$ wall [Press Enter]
Write You Message Here.
Testing Wall OutPut On All Terminals.
Finished

Press Ctrl + D for EOF (End of File)

[root@localhost ~]#
Broadcast message from shankar (pts/3) (Mon Feb 22 12:14:55 2010):

Write You Message Here.
Testing Wall OutPut On All Terminals.
Finished

All Users can view the Message on their Terminal as below

[root@localhost ~]#
Broadcast message from shankar (pts/3) (Mon Feb 22 12:14:55 2010):

Write You Message Here.
Testing Wall OutPut On All Terminals.
Finished

Limitations of Wall :
1. The total length of the message is limited to 22 lines.
2. Broadcasted Messages are limited to The System Itself.

Advantages of Wall
1. During an Activity / Crisis on the system all users can be notified immediately
2. No need to Send Email to the users who are Logged into the System.