rc directories is the old way of managing starting services. The new way is SMF: http://www.princeton.edu/~unix/Solaris/troubleshoot/smf.html
But rc directories still work, for backwards compatibility reasons. rc, basically you create a boot script which is renamed with a number. That number tells when to start that file, the priority in start sequence. First all files with low priority are run, and then higher priority. etc. Google on rc -- This message posted from opensolaris.org
