I want to install Solaris 10 on a Sunblade 150 Machine. It comes on a CD-ROM. Can I install it using an external DVD-drive? 
How do I install Solaris 10 on a Sunblade 150 machine using external DVD drive?
solaris;system installation;opensolaris
Probably not.  As I recall, the last PROM code for the Sun Blade 100/150 didn't support booting from USB devices.  You can buy a 50-pin SCSI DVD-ROM drive from Ebay for anywhere from $20 - $100.  Example: http://www.ebay.com/itm/Pioneer-DVD-116SM-Sun-370-4439-50-pin-SCSI-16x-DVD-ROM-Drive-523424739017-/161001660487?pt=US_CD_DVD_Blu_Ray_Drives&hash=item257c726047The only other option would be to set up a jumpstart server, and boot net - install.