icmp探测 ping baidu.com
tcp探测 nc ip port
powershell -exec bypass Import-Module .\telnet.ps1 Test-PortConnectivity -Source 'localhost' -RemoteDestination '192.168.3.69' -Port 110 -Iterate -protocol TCP
udp探测 powershell -exec bypass Import-Module .\telnet.ps1 Test-PortConnectivity 'localhost' '192.168.3.69' 53 -Iterate -protocol UD
http探测 curl vps-ip:8080
dns探测 windows: nslookup www.baidu.com vps-ip
linux：dig @vps-ip www.baidu.com