How to send message over ssh ubuntu server?

Question

SSH

There is ubuntu server 14, the device connects to this server via ssh. Interested in whether it is possible to send a message to the client in an active ssh session when an event occurs. For example: from a desktop computer via ssh, I connect to the server, do something in the console, and at that moment the power is turned off and the server’s uninterruptible power supply is activated, an emergency message about this event arrives in my console. is that possible?

Answer 1

man wall
man write

Answer 2

linux-notes.org/otpravit-soobshhenie-drugomu-pol-z...

Answer 3

Of course available. This was possible back in the 70s :)
man write (write to someone specific)
man wall (write to everyone who is logged in)