"OpenSolaris started off in early 2005 as Solaris released under the CDDL license. Most of Solaris, that is. A few small parts are still binary-only and not open source, but the kernel and everything people care about are fully open source. The commotion around the CDDL vs. GPL debate you may have heard is that the two are not compatible. Source code developed under the CDDL will likely never find its way into Linux, which means no ZFS or DTrace on Linux. On the bright side, Linux is finding its way into OpenSolaris.
"Ian Murdock, founder of Debian Linux, was hired by Sun to lead Project Indiana. The primary goal of this project was to give OpenSolaris a GNU userland and improved package management system.
"OpenSolaris is not really a fork of Solaris, but rather a new development model. Sun has been criticized for jumping on the open source bandwagon for publicity alone—especially after its MySQL acquisition—but in reality, Sun has fully adopted open source ideals. OpenSolaris development efforts are led by Sun engineers, and improvements do make their way back into Solaris itself. The iSCSI Target support project was the most relevant to me. Community development took off, and very quickly we had iSCSI Target support in Solaris 10, Update 4."
