Nmap

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Nmap (Network Mapper) [1] is a cross-platform (BSD, Linux, Mac, Windows) utility for network discovery and security auditing.

Backgroud

Nmap is a useful tool to find the IP address of a device (e.g. if the device acquired the IP address via DHCP) or to debug connectivity problems (e.g. to check if a firewall blocks ports).

Network discovery example

In a terminal window type:

nmap -v 192.168.1.*

You can specify a specific IP address to scan a single host or use an asterisk (wildcard character) to scan an entire subnet. The resulting output contains a list of discoverd devices with their hostname, IP address and active network ports.

UDP scan example

sudo nmap -v -sU 192.168.0.1

This command scans the UDP ports of a specific device.

References

External links

https://nmap.org