From “Using nmap for Linux administration and security” at http://searchenterpriselinux.techtarget.com/tip/Using-nmap-for-Linux-administration-and-security
nmap “Network Mapper” is a free and open source utility for network exploration or security auditing.
Ping scan to inventory network
nmap -sP -n 192.168.1.0/24
What changed since the last inventory scan?
diff monday.scan tuesday.scan | grep “> Host”
nmap -n -sV 192.168.1.5
Who has ports 80 or 443 open on the network?
nmap -n -p 80,443 192.168.1.0/24 | egrep “ports|open”
What is the state of port 139 on the network?
nmap -n -sV -p 139 192.168.1.0/24 | egrep “ports|139”
Run and test nmap
nmap –A –T4 scanme.insecure.org
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