Here are some great websites/blogs that I follow on a regular or daily basis…
Network Related (routing, switching, etc)
Network Fun!! (by Shane Killen) – An excellent technical blog to visit everyday!
NYC Networkers (run by William Zambrano) – Great resource plus Cisco Cert info!
AmyEngineer (run by Amy) – Lots of VoIP resources along with routing/switching
Krebs on Security (by Brian Krebs) – Visit this site everyday! Just do it…
SANS (Systems Administration and Network Security) – Lots of great resources…
—Internet Storm Center – Daily blog on all things security
—SANS Reading Room – Huge collection of security documents
—Glossary of Security Terms
—Critical Security Controls – If you’re not sure where to start, then start here!!
CentOS – My favorite Linux distro
Redhat – My favorite Commercial distro…it is SOLID as a rock
BIND – DNS server and related tools…highly recommended