Nmap Command Structure.

let's start from the very basics.

Nmap is a powerful network scanning tool used to discover hosts and services active on a computer network or target machine.

Nmap Command Structure

nmap [scan type] [options] [target]

In this command:

nmap: This is the command used to run network scans.
[scan type]: Specifies the type of scan to perform. There are multiple types of scans.
[options]: These are extra settings to make scan more powerful and accurate.
[target]: This is the targeted machine.
- It may be the IP address, website, or network you want to scan.

Example for nmap command:

For now, we pass a target to a server, domain, or IP address.

Target IP address:

nmap -sn 142.250.77.206

Output:

nmap -sn 142.250.77.206
Starting Nmap 7.95 ( https://nmap.org ) at 2025-02-05 15:14 India Standard Time
Nmap scan report for del11s08-in-f14.1e100.net (142.250.77.206)
Host is up (0.043s latency).
Nmap done: 1 IP address (1 host up) scanned in 5.74 seconds

After running this command I got this IP address is active on the internet.

Understanding the Command flow:

nmap -sn 142.250.77.206

When you run this command,

Nmap checks if the target (142.250.77.206) is online. It does this by sending a ping request to the target machine.

The -sn (Ping Scan) option tells Nmap to skip other things and only check if the host is active.

To do this, Nmap sends an ICMP (ping) packet to the target. If the target responds, Nmap confirms that the host is online. If there is no response, the host may be offline or blocking pings.

+--------------------------+      ICMP Ping Request      +--------------------------+
|      Your System         |  ------------------------->  |     Target System        |
|  (Running Nmap)          |     (Are you online?)        |     142.250.77.206       |
+--------------------------+                               +--------------------------+
         |                                                       |
         |         If Target Responds:                           |
         |            "Host is UP ✅"                            |
         |         If No Response:                               |
         |            "Host is DOWN ❌ or Blocking Pings"        |
         |                                                       |
         +-------------------------------------------------------+

Once the scan is complete, Nmap displays the result, showing whether the host is up and how long it took to respond. This is useful when you want to confirm if a system is active before running deeper scans.

Nmap Command Structure.