Although the duties and responsibilities of system administrators vary with the organization, site, and equipment, the basic requirements of the job remain the same. The next few paragraphs will help you find the right tools for your system administration toolbox.
Get Familiar with the Physical Setup
The most important aspect of system administration is familiarity with your network. You must know where the machines are, what they do, how they're connected, and how they're functioning...today. When you first take the position, get someone to give you a tour of the entire installation, with an emphasis on where the information-systems resources are:
Check the location and physical security of your resources. Are they "comfortable" in terms of heat and humidity? Will they be destroyed when the sprinkler system activates? Does the facility have good fire protection?
Are your systems protected from unauthorized physical access? That is, are they located away from the general public, in a locked facility?
During your tour, make sure you find out where all your network cabling runs. This will pay off later when you lose connectivity somewhere and need to know "where the packets are leaking." Are the cables labeled? Be sure to identify all specialty servers (databases, email, application servers) as well as hubs, switches, and routers.