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I have a Ubuntu box and a windowsXP box, both are working well.
But I can't visit some websites(like, in Ubuntu while I can with my other windows box.
Those are just ordinary sites, and I haven't modified hosts files in both boxes for them.
I suppose this has to with dns and stuff, but how to fix it?

There is only one valid line of "nameserver" in /etc/resolv.conf.
When I ping in Ubuntu, it says:
64 bytes from ttl=236 time=55.4 ms
But when I do this in windows it says: Reply from bytes=32 time=47ms TTL=42 Apparently the IP Ubuntu resolved is not correct.

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migrated from Mar 18 '12 at 7:58

This question came from our site for professional and enthusiast programmers.

Actually, that might not be the best example, since that address resolves to different ASNs all over China:

<me>@harley:~$ whois -h " -v"
AS      | IP               | BGP Prefix          | CC | Registry | Allocated  | AS Name
23650   |    |     | CN | apnic    | 2000-03-14 | CHINANET-JS-AS-AP AS Number for CHINANET jiangsu province backbone
<me>@harley:~$ whois -h " -v"
AS      | IP               | BGP Prefix          | CC | Registry | Allocated  | AS Name
4808    |   |    | CN | apnic    | 1998-08-17 | CHINA169-BJ CNCGROUP IP network China169 Beijing Province Network
<me>@harley:~$ whois -h " -v"
AS      | IP               | BGP Prefix          | CC | Registry | Allocated  | AS Name
17431   |   |     | CN | apnic    | 2006-12-06 | TONET Beijing TONEK Information Technology Development Company

However, you've just demonstrated that your boxes are both resolving DNS just fine via your router, which is on address

At this point, I would change the DNS servers that the router is using, if you have the luxury of doing so. and are good candidates, as they're Google's public DNS servers. For the Linux box, you can use nameserver to do this, as well.

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you can check the HTTP connection and raw messages with telnet.

% telnet 80

the host response if connected with HTTP:

Connected to
Escape character is '^]'.

next, type HTTP request in interapt:

GET / HTTP/1.1

and hit the enter key twice.

networking and connection is succeeded if got the document in the web site. thus, the problem is not system configuration. check your browser setting.

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