Hello, after a long time without writing, I finally found the time.

And in another tutorial, we’ll learn how discover open ports or closed on a server, computer …


For this task, we use the command nmap .

According to nmap’s own description, the application is:

Nmap (“Network Mapper”) is an open source tool for network exploration and security auditing. It was designed to track (Scan) large networks quickly yet works well with a single host (host). Nmap uses raw IP packets in (raw) on new ways to determine what hosts (hosts) are available on the net …

For more details you can find in http://nmap.org/ . I like to use nmap, but it does not mean that this is the only way to accomplish this task.

Listing the main server ports

The simplest of commands, just run nmap to the server that you want to investigate

nmap test.com

Listing the main server ports in more detail

nmap -s test.com

Verifying several machines on the network

Very useful for network administrators

Check certain ips
Verifying a track (one range) of IP’s

Verifying a range using wildcard
nmap 192.168.254.*

Verifying a specific port

nmap -p [port] test.com

Verifying a range of ports

nmap -p 80-400 test.com

Again, this is not the only method of doing this scan. And you can find more about nmap the link: http://www.cyberciti.biz/networking/nmap-command-examples-tutorials/

Written by vinicius