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Nmap Tutorial Index

1. Introduction To Network Scanning with Nmap
2. Nmap Installation (Ubuntu, Centos, Fedora, Windows)
3. Nmap Target Specification
4. Nmap Host Discovery
5. Nmap Port Scan (TCP, UDP, ACKi SYNC,..)
6. Nmap Port Specification and Scan Order
7. Nmap Script and Version Scan
8. Nmap Operating System Detection
9. Nmap Timing and Performance
10. Nmap Output

One of the most popular feature of nmap is its Operating System detection from network packets values. To get reliable detection result at least one port of the target should be open.

Enable Operating System Detection

Operating system (OS) detection can be enable with -O . On the other side -A parameter also provides operating system information. To use operating system detection nmap command should be run with root privileges because lower layer network manipulation will be done by nmap.

Enable Operating System Detection

As we see in the example nmap successfully detected the operating system as Linux and the kernel version is 3 or 4 which is correct.

Nmap Tutorial Index

1. Introduction To Network Scanning with Nmap
2. Nmap Installation (Ubuntu, Centos, Fedora, Windows)
3. Nmap Target Specification
4. Nmap Host Discovery
5. Nmap Port Scan (TCP, UDP, ACKi SYNC,..)
6. Nmap Port Specification and Scan Order
7. Nmap Script and Version Scan
8. Nmap Operating System Detection
9. Nmap Timing and Performance
10. Nmap Output