security and rsh

Sorry, my clumsy finders clicked "send" before I could stop them :-)

Here is my question:

Is my setup of the master (the one with 2 NICs) reasonable secure?
IMHO, that is as far as I understand the man pages, no one except the trusted IPs I entered can use rsh on my cluster.

Is that right or are there things I should change/improve?

Kind regards,

Thomas