You probably won't like to hear this, but Enterprise customers seldom use Microsoft for their back end. It's very rare when one considers the current installed base size - typically Windows is the desktop and desktop services applications. The back end systems will be mostly HPUX, Solaris, AIX, and Linux, with Linux predicted to be the dominant enterprise OS in the very near future (say, maybe 2 lease refresh cycles aka 6-8 years).

You should get a linux box or two up and running as soon as possible. Stick MySQL (if you want to work on web stuff) or PostgreSql (compatible with Oracle scripting) on there and get to churning out some configurations. Neither of these will get you experience with things like HANA, but it will enable you to speak and think intelligently about the stack when you meet it in the real world.