I think you have some misconceptions about what’s involved in sysadminning that’s going to make things a lot harder for you. When you’re running a server, you’re running some sort of server (Linux/Win/Solaris/etc). Assuming you want to run a Linux server, that’s still really generic. If you know what services you want to learn (httpd, some RDBMS, some app/lang. runtime, etc.) then you’ll have things narrowed to the point that it’d be easier to point you in a better direction.
I’d really suggest at least 75% hands on time, 25% study that’s not hands on, though, with that focused on security hardening, best practices, configuration, profiling, optimization, and troubleshooting/diagnostics for whatever services you’re learning. There’s really not that much to the theory, but there really are a giant heap of details you’ll only learn with a lot of hands on time. Understanding the UNIX philosophy’s cool, but it isn’t going to get your broken httpd redirect working, tune a database, or help you do much of anything. It’s like learning to play a musical instrument or paint - reading about theory is valuable, but you need most time to be hands on practice if you really want to learn.
