Difference between init runlevel and milestone

Question

Explain difference between init runlevel & milestone?

Answer 1

Up to Solaris 9 runlevel are employed they are Runlevel 0 1 2 3 4 5 6. Within Solaris 10 milestone is introduced. Milestone is advanced level of runlevel

In run level we employ init 1 to bring system in single user, in milestone # svcadm milestone single-user command employed to bring the system to single user likewise init 2 as multi-user (more than one user),init 3 as multi- user-sever provide multiuser mode along with nfs runlevel 4 is presently unused runlevel 5 ie init 5 shutdown and power off runlevel 6 ie init 6 shut down and restart