rwall—Send a message to users logged on a host
The rwall command sends a message to the users logged in to the specified host. The message to be sent can be typed in and terminated with EOF or it can be in a file.
rwall: RPC: Program not registered—The rpc.rwalld(8) daemon has not been started on the remote host.
rwall: RPC: Timed out—A communication error occurred. Either the network is excessively congested, or the rpc.rwalld(8) daemon has terminated on the remote host.
rwall: RPC: Port mapper failure – RPC: Timed out—The remote host is not running the portmapper, and cannot accommodate any RPC-based services. The host may be down.