如何测试端口通不通(四种方法）
一般情况下使用"telnetipport"判断端口通不通，其实测试方法不止这一种，还有很多种方法，下面小编给大家分享了几种方法，具体内容请往下看：
准备环境
启动一个web服务器，提供端口.
[wyq@localhost~]$python-mSimpleHTTPServer8080 ServingHTTPon0.0.0.0port8080...
用其它web服务器提供端口也一样，由于python比较方便，这里就用它
1、使用telnet判断
telnet是windows标准服务，可以直接用；如果是linux机器，需要安装telnet.
用法:telnetipport
1）先用telnet连接不存在的端口
[root@localhost~]#telnet10.0.250.380 Trying10.0.250.3... telnet:connecttoaddress10.0.250.3:Connectionrefused#直接提示连接被拒绝
2）再连接存在的端口
[root@localhost~]#telnetlocalhost22 Trying::1... Connectedtolocalhost.#看到Connected就连接成功了 Escapecharacteris'^]'. SSH-2.0-OpenSSH_5.3 a Protocolmismatch. Connectionclosedbyforeignhost.
2、使用ssh判断
ssh是linux的标准配置并且最常用，可以用来判断端口吗？
用法:ssh-v-pportusername@ip
-v调试模式(会打印日志).
-p指定端口
username可以随意
1）连接不存在端口
[root@localhost~]#ssh10.0.250.3-p80 ssh:connecttohost10.0.250.3port80:Connectionrefused [root@localhost~]#ssh10.0.250.3-p80-v OpenSSH_5.3p1,OpenSSL1.0.1e-fips11Feb2013 debug1:Readingconfigurationdata/etc/ssh/ssh_config debug1:Applyingoptionsfor* debug1:Connectingto10.0.250.3[10.0.250.3]port80. debug1:connecttoaddress10.0.250.3port80:Connectionrefused ssh:connecttohost10.0.250.3port80:Connectionrefused
2）连接存在的端口
[root@localhost~]#ssh...-p a ^] ^C [root@localhost~]#ssh...-p-v OpenSSH_.p,OpenSSL..e-fipsFeb debug:Readingconfigurationdata/etc/ssh/ssh_config debug:Applyingoptionsfor* debug:Connectingto...[...]port. debug:Connectionestablished. debug:permanently_set_uid:/ debug:identityfile/root/.ssh/identitytype- debug:identityfile/root/.ssh/identity-certtype- debug:identityfile/root/.ssh/id_rsatype- debug:identityfile/root/.ssh/id_rsa-certtype- debug:identityfile/root/.ssh/id_dsatype- debug:identityfile/root/.ssh/id_dsa-certtype- a ^C
不用-v选项也可以咯
3、使用wget判断
wget是linux下的下载工具，需要先安装.
用法:wgetip:port
1）连接不存在的端口
[root@localhost~]#wget...: ----::--http://.../ Connectingto...:...failed:Connectionrefused.
2）连接存在的端口
[root@localhost~]#wget...: ----::--http://...:/ Connectingto...:...connected. HTTPrequestsent,awaitingresponse...
4、使用端口扫描工具
[root@localhost~]#nmap...-p StartingNmap.(http://nmap.org)at--:CST Nmapscanreportfor... Hostisup(.slatency). PORTSTATESERVICE /tcpclosedhttp MACAddress:B:A::CF:FD:D(Unknown) Nmapdone:IPaddress(hostup)scannedin.seconds [root@localhost~]#nmap...-p StartingNmap.(http://nmap.org)at--:CST Nmapscanreportfor... Hostisup(.slatency). PORTSTATESERVICE /tcpopenhttp-proxy MACAddress:B:A::CF:FD:D(Unknown) Nmapdone:IPaddress(hostup)scannedin.seconds [root@localhost~]#nmap... StartingNmap.(http://nmap.org)at--:CST Nmapscanreportfor... Hostisup(.slatency). Notshown:closedports PORTSTATESERVICE /tcpopenssh /tcpopenrpcbind /tcpopenhttp-proxy /tcpopenunknown MACAddress:B:A::CF:FD:D(Unknown) Nmapdone:IPaddress(hostup)scannedin.seconds
总结
提供端口服务，则使用了tcp协议，上面是以web服务器为例。如果服务器是更简单的tcp服务器，三个工具同样适用.
三个工具的共同点是：1.以tcp协议为基础；2.能访问指定端口.遵循这两点可以找到很多工具.
一般在windows下使用telnet比较方便，linux下个人就比较喜欢用wget.