You must have console access to all cluster nodes. A service processor (SP) is used to communicate between the administrative console and the global-cluster node consoles.
For more information about console access, see the Oracle Solaris Cluster Concepts Guide .
You can use the Oracle Solaris pconsole utility to connect to the cluster nodes. The utility also provides a master console window from which you can propagate your input to all connections that you opened. For more information, see the pconsole(1) man page that is available when you install the Oracle Solaris terminal/pconsole package.