IDC Says Ex-Unix Shops Love Windows More Than Linux

Published: April 5, 2006

by Timothy Prickett Morgan

The rise of Linux in the data center is often perceived as being the most direct threat to the hegemony of Microsoft's Windows platform and the logical alternative Unix platforms, which are functionally and operationally similar to Linux. It would be reasonable to assume that when Unix shops migrate, they migrate to Linux more than they do to Windows, but a new report from market researcher IDC seems to indicate that when Unix shops move, they tend to move to Windows more than they do to either Linux or another flavor of Unix.

Microsoft commissioned two reports from IDC, one in 2003 and another late last year, to find out what Unix shops were up to when it came to migrating their applications to other platforms. The 2003 study, which was sponsored by Microsoft and another third party who remained anonymous, surveyed 440 Unix shops and profiled their plans, while the 2005 study profiled 400 shops, who were gathered at random from a subset of the Network World magazine subscriber list, companies with RISC/Unix servers, and at least 100 employees were surveyed. According to the survey, 71 percent of the companies in the 2005 survey had Sun Microsystems' Solaris variant installed, down from 80 percent in the 2003 survey, with 55 percent of those polled having IBM's AIX variant installed (down from 56 percent in the early study). Hewlett-Packard's HP-UX variant was at 44 percent of the sites (down from 51 percent) and Tru64 Unix was at 14 percent of those polled (down from 30 percent). Oddly, IDC's surveyors discovered that other Unixes held steady at around 22 percent (up from 21 percent in the 2003 data). Obviously, Unix shops tend to have a mix of Unixes--on average, they have about two different Unix distributions.

What are all of these Unix servers doing? The vast majority of Unix shops polled--83 percent--said they use their Unix machines to run database management systems, with 62 percent using them for "business processing," which could go down as the most vague term any IT analyst ever came up with. IDC found that 40 percent of Unix shops use the platform for decision support applications, 60 percent for application development, 55 percent for infrastructure workloads, and 48 percent for Web infrastructure (which is somehow different from IT infrastructure in the IDC universe). Another 40 percent are using Unix boxes for technical workloads, which usually means supercomputer clusters.

When asked about their propensity to move off Unix to another platform, with some variation based on the type of workload (but not very much), the IDC poll revealed that about 15 to 20 percent of the Unix shops seemed likely to migrate off Unix to another operating system in the next two years, with another 20 to 25 percent somewhat likely to do so. Roughly 55 to 60 percent of Unix shops have no intention of moving, which explains the persistence of Unix as a dominant server platform, even given the phenomenal growth of the Windows platform (which has passed Unix to become the top platform by aggregate revenue and already far exceeds Unix platforms in terms of shipments) and the onslaught of the very Unix-alike Linux platform (which will probably soon be the only growing server platform in the world). In terms of when Unix platforms are facing the highest likelihood of migration, IDC found that around 55 to 60 percent of customers using SCO Unix, Tru64 Unix, and other Unixes think it somewhat likely or highly likely that they will move off that Unix in the next three years. About 40 percent of AIX, Solaris, and HP-UX shops said they were somewhat or highly likely to move.

For database workloads, generally speaking, Unix shops running database and decision support applications tend to prefer to move to another Unix platform, while for other workloads Windows and Linux seem to be holding neck-and-neck for ex-Unix shops.

"Overall, the size of the Unix installed base appears to be flattening because of slowing unit volume growth and recent migration efforts within the worldwide Unix installed base," says Matt Eastwood, vice president of IDC's server research. "On a unit basis, Windows becomes the top migration platform overall, with 45 percent of these migrating footprints. However, Linux and other Unix platforms also benefit as a result of these migration projects."

IDC took a stab at estimating the size of the worldwide Unix server replacement market for the coming year, and thinks that 530,000 servers will be unplugged and customers will spend some $4.8 billion moving to a new platform. In terms of shipments, Windows will get 44.8 percent of those units, or about 237,440 machines, while Linux will get 37.1 percent, or about 197,743 machines. Movement from one Unix variant to another will account for another 16.3 percent of shipments, or 86,390 boxes, and the remaining other 1.8 percent of shipments of replaced Unix footprints (about 9,540 boxes) will be for the few companies that move their Unix workloads to IBM mainframes or iSeries servers. While Windows wins as the Unix replacement platform by footprint, the amount of revenue generated by those Unix-to-Unix migrations will come to 47.9 percent of the sales related to these jumps, or about $2.3 billion. Linux will only account for about $850 million in sales from former Unix platforms (17.8 percent of the pie), while Windows will account for just over $1 billion in ex-Unix sales (21.3 percent). That tiny "Other" category in the footprint pie balloons up to be $620 million, or about 13 percent of the pie.

The interesting thing in this report is that it confirms something I have been saying for years: While all of the server vendors make a lot of noise about competitive replacements, very little of the server market seems to be in play. A little more than half a million units in a market that will consume well over 8 million server units in 2006 and an installed base of probably 25 million units (those are my estimates for 2006 shipments and the installed base, not IDC's) is not a very large number. That said, there are billions of dollars at stake in doing competitive replacement, and all the vendors have to chase it.