Before I got deeply involved in Oracle I was a UNIX system admin. Our main servers were Sun Solaris. They are the most stable and powerful servers of their type. We too had a server up 2.5 years plus! THAT is the kinda system you want a business to run on!
Oracle, who now owns Solaris, have added a new kernal to their LINUX that allows you to restart any part of the kernal while keeping the OS up. Zero downtime mission statement there!
That HiTech use Solaris for part of their mission critical services shows you guys just how dedicated they are to performance and stability. If you only look at impact fees and not ROI, Windows would have been much cheaper. Very wise move by HiTech to use Solaris.
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Slade