Hi, I was an IT professional working with Document Management software and doing Systems Administration for a few years (all for small companies less than 25 employees each). Last year, I decided to go back to my core profession (Electrical Engineering) but have found I am doing a lot of IT work anyway, just with outdated technology (Windows 2000, older machines, etc.). I now want to return to IT but want to work with state of the art systems and for a big company (perhaps as part of an IT team) doing what I feel I specialize in, which is building and configuring servers and workstations. Having always worked in smaller environments, I feel I may not have enough knowledge to do Systems or Server Administration in a large environment. I'm turning to this forum for some advice as to how to go about getting back into the IT field and what sort of topics to focus on for the interviews that will hopefully lie ahead soon. Thank you in advance for your comments and suggestions.

big shot high end topics (can be googled/wiki-d):
storage - san, das, iscsi / netapp / emc
security - great big bunch of things
servers - blades / hardware level virtualizations, i.e. VMWare ESX / clustering (HA, failover, computation)
Databases - Oracle mostly
Unix/Linux

for me personally it took many years and loads of experience to get access to any of those. generally nobody needs a small company system admin in a large company, because for those you (as I some time back) are just a pc tech with basic server knowledge.
the hottest topic right now is virtualization and iscsi/san. they all require experience and proper certifications. all those cost loads of money.

good luck.

You really do have to start small and work your way up. Not only do you need the experience, but it's better to start off small, and then work your way to big so you don't jump in over your head and screw anything up . It also gives you the opportunity to refresh your skills and make sure you're on top of the game as far as advances that have come in and having that experience to back up the knowledge does a lot to convince prospective employers that you can walk the talk and know enough to take on their bigger systems.

Thank you both (jjaydnn and DimaYasny) for your responses; I will keep what you both have said in mind as I begin my search.