This was the last Cray OS really based on UNICOS sources, as the following products were based on different sources and simply used the "UNICOS" name. UNICOS/mp: not derived from UNICOS, but based on IRIX 6.5. Used on the X1. UNICOS/lc: not derived from UNICOS, but based on SUSE Linux. Used on the XT3, XT4 and XT5. UNICOS/lc 1.x comprises a combination of the compute elements run the Catamount microkernel (which itself is based on Cougaar) the service elements run SUSE Linux Cray Linux Environment (CLE): from release 2.1 onward, UNICOS/lc is now called Cray Linux Environment the compute elements run Compute Node Linux (CNL) (which is a customized Linux kernel) the service elements run SUSE Linux Enterprise Server See also Scientific Linux, a Linux distribution by Fermilab and CERN Rocks Cluster Distribution, a Linux distribution for supercomputers References 1984 software Cray software Linux distributions Microkernel-based operating systems Microkernels Supercomputer operating systems Unix distributions UNIX System V