Unix Tip: Port scanning with nmap

By Sandra Henry-Stocker

A number of weeks ago, I provided and described a script that uses nmap to quickly scan a system or subnet for activity on a particular port. Useful for detecting, say, web servers or Oracle installations, the script runs very quickly and provides a useful table of host names, IP addresses and the name of the service being sought. In this week's column, we look a little more deeply into nmap, what it can do for you and some of the scans that it can perform.

Read the full article here.