1, to detect whether the specified network segment FTP service host, do not do DNS reverse analysis

nmap -sS –n –p 21 192.168.0.0/24 2, to detect whether the specified server has a specific port services

nmap –n –p T:21-25,80,110,3389–sS 192.168.0.1

3, the use of TCP connection scan to detect the specified server, even if it […]