协议：ICMP、TCP、UDP、http、DNS
ICMP
ping ip/domain tracert ip/domain ping www.baidu.com # ICMP tracert baidu.com # ICMP
TCP/UDP
telnet ip port nc -zv ip port nc -zuv ip port telnet 192.168.1.108 22 # TCP nc -zv 192.168.1.108 80 # TCP nc -zuv 192.168.1.108 80 # UDP
HTTP/HTTPS
curl ip or domain curl http://www.baidu.com # HTTP curl https://www.baidu.com # HTTPS Linux: wget curl Windows: certutil powershell bitsadmin regsrv....
DNS
linux： dig @8.8.8.8 www.baidu.com #DNS windows： nslookup www.baidu.com 8.8.8.8 #DNS
参考：http://aiyuanzhen.com/index.php/archives/232/
