SunOS 4.1.2
SunOS 4.1.2 (also known as Solaris 1.0.1) is a version of SunOS released in December 1991. Support for multiprocessor (SPARCserver 600MP) systems have been introduced in this version. It is also the first version of SunOS to distributed only via CD-ROM. Support for multiprocessors with the sun4m architecture has been added.