Mastering the Nmap Scripting Engine

Appendix A. Scan Phases

Scans performed with Nmap are divided into phases, and some of them may be skipped using different Nmap options. The scan phases of Nmap are:

• Script pre-scanning: The pre-scanning phase is executed only when you use the -sC or --script options; it attempts to retrieve additional host information via a collection of NSE scripts.
• Target enumeration: In this phase, Nmap parses the target (or targets) and resolves them into IP addresses.
• Host discovery: This is the phase where Nmap determines whether the target (or targets) is online and in the network by performing the specified host discovery technique (or techniques). The -Pn option can be used to skip this phase.
• Reverse DNS resolution: In this phase, Nmap performs a reverse ...