TCP端口的连通性
方法一:TCP协议是面向连接的,可以直接通过telnet命令连接
telent ip port ➜ packages telnet 127.0.0.1 80 Trying 127.0.0.1... Connected to 127.0.0.1. Escape character is '^]'.
方法二:使用nc(netcat)命令
nc -vz ip port ➜ packages nc -vz 127.0.0.1 80 found 0 associations found 1 connections: 1: flags=82<CONNECTED,PREFERRED> outif lo0 src 127.0.0.1 port 49594 dst 127.0.0.1 port 80 rank info not available TCP aux info available Connection to 127.0.0.1 port 80 [tcp/http] succeeded! ➜ packages nc -zv 127.0.0.1 8080 nc: connectx to 127.0.0.1 port 8080 (tcp) failed: Connection refused
nc相关option:
-u UDP mode -v Verbose -z Zero-I/O mode [used for scanning]
UDP端口的连通性
UDP协议是无连接的,不需要握手建立连接,数据发送后,server端也不会返回确认信息。
方法一:使用nc(netcat)命令
nc -uvz ip port ➜ packages nc -uvz 127.0.0.1 80 found 0 associations found 1 connections: 1: flags=82<CONNECTED,PREFERRED> outif (null) src 127.0.0.1 port 54152 dst 127.0.0.1 port 80 rank info not available Connection to 127.0.0.1 port 80 [udp/http] succeeded!
总结:nc(netcat)是专门用于TCP/UDP连接和监听的命令,建议大家直接使用nc。
您可能感兴趣的文章:
如您对本文有疑问或者有任何想说的,请 点击进行留言回复,万千网友为您解惑!
网友评论