Note the following changes to the init command:
SunOS release 5.6 system software has eight initialization states (init states or run levels). The default init state is defined in the /etc/inittab file.
The SunOS release 5.6 init command uses a different script for each run level instead of grouping all the run levels together in the /etc/rc, /etc/rc.boot, and /etc/rc.local files. The files, named by run level, are located in the /sbin directory.
System Administration Guide describes this command in detail.