Those still running NT4 face the choice of migrating to alternative operating systems or running the server unsupported. Although datacentre and mission-critical systems are likely to have been migrated already, analyst firm Gartner estimates that 35% of users will still have an NT4 server running in their businesses.
Gartner research director Ian Brown said many of those users could find themselves running the NT4 server unsupported during 2005 because they have been unable to keep track of the configuration of all the servers they have deployed.
Microsoft has recommended migration from NT4 to Window Server 2003, but Brown said some users are seriously considering Linux instead. "With a non-mission critical workload, Linux is attractive as support is available informally and it can run [in a basic] OS environment," he said.
Another option for users is to choose virtualisation technology such as VMWare or Microsoft Virtual Server 2005, which allow a server to run multiple operating systems as partitions on the same physical hardware.
Richard Edwards, research analyst at Butler Group, said, "With Virtual Server running on a high-end box, users can consolidate servers and run NT4 on partitions."
Users may be reluctant to change their NT4 systems because of the inherent stability of the operating system, which has been supported since 1996 with eight years' worth of patching and hotfixes.
Edwards said, "If an operating system has been running for a number of years and has not exposed the business to risks, it can continue to run."
Although new source code fixes are unlikely to be issued, he said users would still be able to access Microsoft's online support, containing published fixes and workarounds.