Sometimes we need to notify another users connected by SSH in same server with a simple message like when we use ‘halt‘ or ‘init 0‘ commands. Ubuntu-based distros have a special program to it, it’s wall. Then, to send a broadcast message for all connected users in server terminal, you can use:
[bash]echo “Buy more beers guys” | wall[/bash]
Now, all of SSH users will receive a message like this:
Broadcast Message from carlos@server-rel
(/dev/pts/0) at 13:53 ...
Buy more beers guys