奇怪的网络问题

grins

就是可以正常使用网络，80，21，23等等应用都可以正常访问

sitxw

I think:\r\n1.you can check Browser.\r\n2.Reduce MTU value.\r\n\r\nJust my suggestion.

briangao

Your network may not have problem at all. Try telnet www.sina.com.cn and then type get and then enter return key twice. Tell me what you get.

FOR_FREE

本地有DNS　　SERVER么？

grins

使用的本地dns解析，好像和dns没有关系。

briangao

This seems to be a specific problem for sina. Can you access other websites? 218.30.66.121  is sina\'s server in Bejing. Try their Shanghai\'s server (61.172.201.195) to see whether you can access or not

grins

试过很多网站了，都不行啊

FOR_FREE

你的DNS　SERVER可以上外网么？我觉得是这样，你能PING通并不代表你能上外网，因为你是通过本地的DNS　SERVER解析的，而且刚刚你说了可以上内网，你把DNS　SERVER　设成外网的DNS看能不能正常。

FOR_FREE

我上面想错了~~你的PING包是从哪里来的呢？？有没有sniffer看一下~

briangao

The IP address you are using is RFC1918 private IP. In order for you to access internet, your firewall must do NAT ( network address translation). Can you verify with your network admin how your natting is setup? If the natting is setup correctly, can you ask them to check the firewall log regarding the return packet ?