Linux Network Information Gathering Lecture (part 2)

Virtual Practice Lab
Practice Test
Linux Network Information Gathering Lecture (part 2)

This lessons covers port specification and scan techniques and discusses the following examples:

  • -p <port range>: only scan specific ports
  • -F: fast mode. Scan fewer ports than the default scan.
  • -r: scan ports consecutively. Don’t randomize.
  • Top ports <number>: scan <number> most common ports
  • Port ratio <ratio>: scan ports more common than <ratio>

Participants also learn about service/version detection:

  • sV: probe open ports to determine service/version info
  • version intensity <level>: set from 0 (light) to 9 (ty all probes)
  • version light: limit to most likely probes (intensity 2)
  • version all: try every single probe (intensity 9)
  • version trace: showed detailed version scan activity (for debugging)

This lesson also discusses P0f is passive OS fingerprinting and listens to traffic with the intention of identifying operation systems and does not generate its own traffic as well as Tcpdump which prints out a description of the contents of packets on a network to match the Boolean expression.

Recommended Study Material


Learn on the go.
The app designed for the modern cyber security professional.
Get it on Google PlayGet it on the App Store
Practice Labs and Exam Vouchers

Congratulations! You're taking the first step to getting certified. Get some hands on experience with available practice labs OR save some money, support Cybrary, and purchase discounted exam vouchers. Ready to earn your next industry certification? Join cyber security's largest community and start learning today.


Our Revolution

We believe Cyber Security training should be free, for everyone, FOREVER. Everyone, everywhere, deserves the OPPORTUNITY to learn, begin and grow a career in this fascinating field. Therefore, Cybrary is a free community where people, companies and training come together to give everyone the ability to collaborate in an open source way that is revolutionizing the cyber security educational experience.

Cybrary On The Go

Get the Cybrary app for Android for online and offline viewing of our lessons.

Get it on Google Play

Support Cybrary

Donate Here to Get This Month's Donor Badge

Skip to toolbar

We recommend always using caution when following any link

Are you sure you want to continue?