Nmap port scanner

Port scanning is the process of checking for open TCP or UDP ports on a machine.Please note port scanning is  illegal in many countries and should be performed inside virtual labs.

DNS Zone transfers using Dig

Zone transfers (AXFR) will allow you to pull an entire record set down from a nameserver at once. If successful, you will be provided with a listing of all information on the nameserver from one simple command.

DNS lookup commands

DNS offers a variety of information about public and private organization servers, such as IP addresses, server names and server functions. A DNS server will usually divulge DNS and Mail server information for the domain which it is authoritative.

Google Hacking Techniques

Google hacking was first introduced by Johnny Long, who has since published a book about it called “Google Hacking” - a must for any serious Googlenaut.

Reconassiance

Penetration testing is most effective when you have a good grasp on the environment being tested. Sometimes this information will be presented to you by the corporation that hired you, other times you will need to go out and perform your reconnaissance to gather information.