But times have changed and Larry Ellison's recent announcement that Oracle plans to move its own business away from HP servers and instead migrate to a much cheaper Linux cluster of Intel-based servers, encouraged Merrill Lynch to worry about Sun's lucrative Unix business being "attacked from below by Intel servers running both NT and Linux.
"In our view, Linux is a greater threat to Sun than Microsoft because Solaris programmers can more easily learn Linux," said the industry analyst.
Facing the unerring advance of Windows 2000 Advanced Server, Sun has had far more reason to be worried by Microsoft than the relatively slow growth of the Linux market. And when Larry Ellison announces the inevitability of a new technology trend most of us can calmly bet on the opposite happening - Network Computers, Raw Iron, need I say more?
However, Ellison may be on track in predicting the death of large servers, with the arrival of server blades and server appliances. Oracle is reportedly already working with Linux distributor Red Hat to offer its own application server pre-configured.
News like this leaves Sun with a foot on either side of a widening crevasse, watching Linux working its way up the enterprise much like an elevator.
Sun, facing the inevitability of Linux, is having to reconcile the operating system with its own product line or risk watching its customers drift away over time.
It has been suggested that Sun may have suspended further development of its x86 Solaris to make way for Linux from its recently acquired Cobalt unit. The company is shipping built-in Linux compatibility with Solaris already.
Embracing Linux gives Sun two immediate problems. You cannot become a little bit pregnant with Linux - you are either in the club or you are not - and Linux brings with it the vocal opinions and standards of an established global community that Sun will not be able to steamroller and ignore as it did with Java.
Linux also conjures-up a word that is quite unattractive to Sun: "cheap". Indeed, once Linux starts to creep onto servers at one level, its quite likely that cost-conscious corporate accounts will start asking if they can have Linux on successive steps up the server ladder.
With IBM's support for the open source operating system starting to resemble a vice-like grip on its future, Sun is having to redefine its business or watch IBM eat its lunch.
Simon Moores is chairman of the Research Group www.zentelligence.com