database administration - Linux knowledge a Junior cannot miss

I am soon going to be graduating from college, and am looking for job offers right now. There is one that I have a lot of interest in, involving Linux system administration (PHP, MySQL, Apache Webserver, BIND, bash, postfix, and of course general system maintenance and security).

However, during my internship most of my assignments involved Hyper-V virtualization and Windows in general, and I didn't get much Linux-time. In my spare time, I'm usually a windows user as well with only very basic Linux knowledge.

What knowledge and skills would you say a new Junior job applicant needs to posess before he is really ready for the job (and the interview)? Any sources, going from books to e-books, tutorials, general skill descriptions, commands, websites, blogs, ... will help me a bunch.

Help me become a better Linux administrator, and getting ready for this interview!
Thanks a lot :-)

EDIT: As some people suggested, I'll update the original question: I stated that I am a Junior in the question title, and that refers to the title of the job I am applying for (without experience, there's almost no chance you'll get a job as a Senior, obviously). My Linux knowledge might be a bit better than I let you guys understand; I am way past the "how do I set up a dns server?" stage, dns, dhcp, webserver etc, I've set those up before several times.

I am looking for more advanced knowledge, stuff I'll need in my daytime job, or questions I may be asked in a job interview. I want to be prepared for it as I can be.

Thanks for the input so far!

Answer

There's already plenty of information(Questions/Posts) in ServerFault for a beginner Linux administrator:

In addition, I will suggest you find an old computer and install Linux on it. Play with it, setup a firewall, DNS, DHCP on it to start and test things. You could even set it up in a VM and do stuff in it. Nothing is going to help you better than getting yourself in there for the real experience. Decide of a good use for it and try to use it as much as you can. Ask questions when you get stuck (research it first, though), that's why we're here for.