Distributing a scan among several clients using Dnmap
Dnmap is an excellent project in order to distribute Nmap scans among different clients. The extra resources available (CPU and bandwidth) allow us to scan more targets faster when time is a limiting factor. Although there are other port scanners designed for speed, Dnmap has the advantage of having the Nmap Scripting Engine script arsenal available.
The following recipe will show you how to perform distributed port scanning with Dnmap.
Getting ready
Download the latest version of Dnmap from the official SourceForge repositories at https://sourceforge.net/projects/dnmap/files/.
Dnmap depends on Python's twisted
library. If you are on a Debian-based system, you can install it with the following command:
#apt-get install libssl-dev python-twisted
It is also worth mentioning that Nmap is not self-contained in Dnmap; we must install it separately on each client. Please refer to the Compiling Nmap from source code recipe in Chapter 1, Nmap Fundamentals...