I'm trying to find a way to broadcast a shutdown message to all the users on clients connected to my centos server. The wall command sends only to users logged into the server and not to clients .I know also of rwall but can't seem to find it on centos 6 or a package that provides it .Is there a cleaner way to do this in rhel/centos 6 .
Shutdown includes an optional message paramater
So if I wanted to restart in 60 minutes and notify all my users I would use
shutdown -r +60 Attention all Linux Users, the system will need to be restarted for maintenance soon!