Sun Microsystems is guiding the spotlight away from a once-prominent feature of Solaris 10.
The feature, code-named Janus and not yet released, lets Linux applications run on its Solaris operating system. Sun instead is emphasising a related open source alternative called Xen.
Sun had touted Janus as a useful tool to help customers drop Linux in favour of Solaris, Sun's version of Unix. Sun offers the software to interested customers, but now expects customers that run Linux applications to be more interested in an ordinary version of Linux.
"The interest in doing Linux applications on Solaris has been for migration. But when you talk about running certified data centre applications, you're going to run that on the full stack of software that's been certified," said Tom Goguen, director of Solaris marketing for Sun.
Running Linux and Solaris side-by-side on the same computer will be possible with an open source project called Xen, 'hypervisor' software that lets multiple operating systems run simultaneously on one computer. It's used chiefly with Linux today, but "We've gotten actively involved in the Xen project," Goguen said.
Though Sun expects Xen to be more widely used, the company plans to offer and support Janus, Goguen said. John Fowler, a Sun executive vice president, said he's helped out Xen developers: "I just sent them a pile of hardware, gratis." And Solaris programmer Tim Marsland, in his blog on Friday, invited others to help Sun build Xen support into OpenSolaris.
IBM, Hewlett-Packard, Intel and Advanced Micro Devices also are Xen enthusiasts. Microsoft, which is critical of the General Public License (GPL) that covers open source Xen, has its own hypervisor work under way.
Janus, officially called the Linux Application Environment, translates Linux commands to Solaris commands so Linux programs can run unmodified on computers using x86 processors such as Intel's Pentium and AMD's Opteron. It's part of Sun's effort to turn the competitive tables on Linux.
In November, Sun boasted, "Solaris 10 will be the only OS to run Solaris and native Linux binaries side-by-side with no modifications, providing customers with investment protection and broader access to applications written for both operating systems." Sun had planned to include it in an update to Solaris, starting with compatibility for Red Hat Enterprise Linux and later expanding to Suse Linux Enterprise Server.
Janus had been expected in 2005, but it was delayed until 2006 along with new storage software called ZFS, or Zettabyte File System.
