There are many reasons to switch from Linux to Unix. Perhaps the biggest selling point with Linux is that it gives you choices. From hardware to support to Linux distributions, you have a multitude of choices to make. You can run Linux on a $200 used-PC, you can run it as an LPAR (logical partition) on a million-dollar p595 IBM pSeries server (you must make the choice between RHEL4 or SLES9), an IBM mainframe or a SUN T2000 server.
With Linux, you are no longer held hostage to the whims of your hardware distributor. Though Unix is marketed as an open system, the reality is that you are usually married to the hardware vendor. The open sourcing of Solaris has stirred the pot a bit, but Linux has been and continues to be at the forefront of all mid-range innovation. Have you ever had to wait weeks or months for the latest fix-pack to come out from your vendor to fix an OS bug? With Linux, you might wait days or even hours. The open source community can deliver with lightning speed what takes endless development cycles to be done with Unix. Furthermore, just about very major ISV today has or is coming out with a Linux version of their software. Linux market share is on the upswing and people are asking for it.
You are entitled to your opinion with regards to your favorite Unix flavor, though the market does not concur, as IBM has overtaken Sun in server sales and IBM's virtualization capabilities and high-end server offerings clearly out-perform anything that Sun has at this time. While Unix servers experienced an overall 1.6% decline in revenue (1.8% in shipments) in the second quarter of 2006, Linux servers and Windows servers continued to grow unit shipments at double-digit rates, while revenue growth for both types of servers moderated to single-digit growth.
The Unix market is still huge and the three major players are fighting tooth and nail for market share. IBM secured the top spot in 2005, with 31.8% of the market to Hewlett-Packard's 29.8 % and Sun's 26.2 %, while Windows servers overtook Unix servers for the first time in 2005, selling $17.7 billion worth of Windows servers worldwide in 2005 compared with $17.5 billion in UNIX servers. In yet another first, Linux took third place, bumping spots with IBM's mainframe operating system, z/OS. Linux server sales grew from $4.3 billion in 2004 to $5.3 billion in 2005, while mainframes dropped from $5.7 billion to $4.8 billion over the same period.
IBM now ranks number one in overall Linux-based server revenue. More than any other hardware vendor, IBM promotes Linux in a big way. IBM hosts free APV across the country with labs that let people install Linux partitions. IBM's promotion of Linux is real, and perhaps more importantly, IBM's Linux technology is groundbreaking
This was first published in December 2006