"Think of Linux security as a sort of "wedding cake". The two
figures at the top are the root account. As a user (authorized or
unauthorized) tries to gain more privileges leading up to root, it
should be increasing difficult. Your objective is to add as
many rings or layers as possible, making the potential cracker take
more time to get in (and increasing the chance of you noticing and
stopping him before he roots you.)"
"1. Physical Security
If sending this box to a colocation provider to put it on the Net,
remember that others WILL be around your machine. While most colo
providers are pretty good about making sure that people in the
facility don't touch other people's computers, your aim should
still be minimize the risk."
"2. Network Security
This is a big area. I can't cover it all in this article! Here are