I have configured IPv6 on Windows XP SP2 and assigned a global address on my 
ethernet NIC which is routed to the IPv6 Internet.

When I try to load a web page in Internet Explorer 7, the page does not 
load, it just says "Connecting..." and the circle keeps spinning. I get the 
same thing with Firefox 2.

However, I can telnet to port 80 on the IPv6 address of the host and 
manually enter a "GET / HTTP/1.0" and get served the page instantly. So it's 
not a connectivity issue.

Sniffing the packets going through my router, I see that the initial TCP 
handshake is performed, but the browser never sends a request:

22:57:52.839389 IP6 (hlim 128, next-header: TCP (6), length: 24) 
2001:470:1f07:316::2.1041 > 2001:5c0:0:1::6.80: S, cksum 0xd374 (correct), 
2196410878:2196410878(0) win 16384 <mss 1220>
22:57:53.077967 IP6 (hlim 117, next-header: TCP (6), length: 24) 
2001:5c0:0:1::6.80 > 2001:470:1f07:316::2.1041: S, cksum 0x441e (correct), 
2508454117:2508454117(0) ack 2196410879 win 16384 <mss 1440>
22:57:53.078280 IP6 (hlim 128, next-header: TCP (6), length: 20) 
2001:470:1f07:316::2.1041 > 2001:5c0:0:1::6.80: ., cksum 0x590f (correct), 
1:1(0) ack 1 win 17080

I'm stumped what could be wrong that is affecting both Internet Explorer and 
Firefox but not telnet to port 80. I have removed anti-virus software for 
what that's worth.

Any ideas?

David

David Madole wrote:
> I have configured IPv6 on Windows XP SP2 and assigned a global address on my 
> ethernet NIC which is routed to the IPv6 Internet.
> 
> When I try to load a web page in Internet Explorer 7, the page does not 
> load, it just says "Connecting..." and the circle keeps spinning. I get the 
> same thing with Firefox 2.
> 
> However, I can telnet to port 80 on the IPv6 address of the host and 
> manually enter a "GET / HTTP/1.0" and get served the page instantly. So it's 
> not a connectivity issue.

it *IS* a connectivity issue. You have MTU issues there.

Somewhere in the path between you and them there is a box which has either:
  - a misconfigured MTU (thus the ends disagree on it)
  - is filtering ICMPv6 "Packet Too Big" messages

The way to test that is to try and get a file off HTTP which is smaller 
than 1280 bytes.

Possible Solutions:
  - tracepath6 (available on most Linuxes):
     this will tell you if/where there is a MTU problem
  - normal traceroute6
     if a hop is filtering ICMP this will also pop up there

But getting that path completely fixed is generally quite difficult as 
you need to contact every single hop along the path to figure out where 
it happens if tracepath6 doesn't make it directly visible.

Greets,
  Jeroen

David Madole wrote:
> I have configured IPv6 on Windows XP SP2 and assigned a global address on my 
> ethernet NIC which is routed to the IPv6 Internet.
> 
> When I try to load a web page in Internet Explorer 7, the page does not 
> load, it just says "Connecting..." and the circle keeps spinning. I get the 
> same thing with Firefox 2.
> 
> However, I can telnet to port 80 on the IPv6 address of the host and 
> manually enter a "GET / HTTP/1.0" and get served the page instantly. So it's 
> not a connectivity issue.

it *IS* a connectivity issue. You have MTU issues there.

Somewhere in the path between you and them there is a box which has either:
  - a misconfigured MTU (thus the ends disagree on it)
  - is filtering ICMPv6 "Packet Too Big" messages

The way to test that is to try and get a file off HTTP which is smaller 
than 1280 bytes.

Possible Solutions:
  - tracepath6 (available on most Linuxes):
     this will tell you if/where there is a MTU problem
  - normal traceroute6
     if a hop is filtering ICMP this will also pop up there

But getting that path completely fixed is generally quite difficult as 
you need to contact every single hop along the path to figure out where 
it happens if tracepath6 doesn't make it directly visible.

Greets,
  Jeroen

"Jeroen Massar" wrote:

> it *IS* a connectivity issue. You have MTU issues there.
> 
> Somewhere in the path between you and them there is a box which has either:
>   - a misconfigured MTU (thus the ends disagree on it)
>   - is filtering ICMPv6 "Packet Too Big" messages
> 
> The way to test that is to try and get a file off HTTP which is smaller 
> than 1280 bytes.

That doesn't make any sense since my end never sends the request, so it 
makes no difference what size the response is. If you look at my original 
post, I show that that only packets sent are the TCP handshake but the 
browser never sends the actual "GET / HTTP/1.1" request for data.

I did try what you suggest though anyway. I tried loading 
http://go6.net/4105/images/icon_world.gif which is a 321 byte gif image and 
was unable to. The total response size with headers and all is 572 bytes when 
requested via IPv4. On IPv6 I see the same behavior, the browser never even 
sends the GET request.

David

"Jeroen Massar" wrote:

> it *IS* a connectivity issue. You have MTU issues there.
> 
> Somewhere in the path between you and them there is a box which has either:
>   - a misconfigured MTU (thus the ends disagree on it)
>   - is filtering ICMPv6 "Packet Too Big" messages
> 
> The way to test that is to try and get a file off HTTP which is smaller 
> than 1280 bytes.

Also, IPv6 works fine with Opera, loading any size page.

I believe this issue may be related to wininet since Internet Explorer and 
Firefox both use it and I suspect that Opera does not.

David

David Madole wrote:
> "Jeroen Massar" wrote:
> 
>> it *IS* a connectivity issue. You have MTU issues there.
>>
>> Somewhere in the path between you and them there is a box which has either:
>>   - a misconfigured MTU (thus the ends disagree on it)
>>   - is filtering ICMPv6 "Packet Too Big" messages
>>
>> The way to test that is to try and get a file off HTTP which is smaller 
>> than 1280 bytes.
> 
> Also, IPv6 works fine with Opera, loading any size page.
> 
> I believe this issue may be related to wininet since Internet Explorer and 
> Firefox both use it and I suspect that Opera does not.

Firefox might link to wininet.dll but it is not using (afaik from last 
time I checked) that for opening sockets.

Is Opera really using IPv6, and when it is, is it using the same 
source/dest pair as it would for firefox?

Also, try a different connection point and remote website, preferably 
keeping src/dst inside the same network.

Greets,
  Jeroen

David Madole wrote:
> "Jeroen Massar" wrote:
> 
>> it *IS* a connectivity issue. You have MTU issues there.
>>
>> Somewhere in the path between you and them there is a box which has either:
>>   - a misconfigured MTU (thus the ends disagree on it)
>>   - is filtering ICMPv6 "Packet Too Big" messages
>>
>> The way to test that is to try and get a file off HTTP which is smaller 
>> than 1280 bytes.
> 
> Also, IPv6 works fine with Opera, loading any size page.
> 
> I believe this issue may be related to wininet since Internet Explorer and 
> Firefox both use it and I suspect that Opera does not.

Firefox might link to wininet.dll but it is not using (afaik from last 
time I checked) that for opening sockets.

Is Opera really using IPv6, and when it is, is it using the same 
source/dest pair as it would for firefox?

Also, try a different connection point and remote website, preferably 
keeping src/dst inside the same network.

Greets,
  Jeroen

David Madole wrote:
> "Jeroen Massar" wrote:
> 
>> it *IS* a connectivity issue. You have MTU issues there.
>>
>> Somewhere in the path between you and them there is a box which has either:
>>   - a misconfigured MTU (thus the ends disagree on it)
>>   - is filtering ICMPv6 "Packet Too Big" messages
>>
>> The way to test that is to try and get a file off HTTP which is smaller 
>> than 1280 bytes.
> 
> Also, IPv6 works fine with Opera, loading any size page.
> 
> I believe this issue may be related to wininet since Internet Explorer and 
> Firefox both use it and I suspect that Opera does not.

Firefox might link to wininet.dll but it is not using (afaik from last 
time I checked) that for opening sockets.

Is Opera really using IPv6, and when it is, is it using the same 
source/dest pair as it would for firefox?

Also, try a different connection point and remote website, preferably 
keeping src/dst inside the same network.

Greets,
  Jeroen

"Jeroen Massar"  wrote in message 
news:47B01A8E.5030607@spaghetti.zurich.ibm.com...
> David Madole wrote:
>> I have configured IPv6 on Windows XP SP2 and assigned a global address on 
>> my ethernet NIC which is routed to the IPv6 Internet.
>>
>> When I try to load a web page in Internet Explorer 7, the page does not 
>> load, it just says "Connecting..." and the circle keeps spinning. I get 
>> the same thing with Firefox 2.
>>
>> However, I can telnet to port 80 on the IPv6 address of the host and 
>> manually enter a "GET / HTTP/1.0" and get served the page instantly. So 
>> it's not a connectivity issue.
>
> it *IS* a connectivity issue. You have MTU issues there.
>
> Somewhere in the path between you and them there is a box which has 
> either:
>  - a misconfigured MTU (thus the ends disagree on it)
>  - is filtering ICMPv6 "Packet Too Big" messages
>
> The way to test that is to try and get a file off HTTP which is smaller 
> than 1280 bytes.

I always thought that MTU problems are gone with IPv6. Minimum size and pmtu 
etc?

Furthemore: shouldn't a big paket be sent at least once? The trace only 
shows pakets with 20-24 length..

-- 
Jens

Le samedi 12 avril 2008 15:24, Jens Weibler a écrit :

> I always thought that MTU problems are gone with IPv6. Minimum size and
> pmtu etc?

Of course NOT.

MTU problems are inherent to any packet switched network, whatever the
protocol. IPv6 differs from IPv4 only in forbidding on-path fragmentation.
In other words, IPv6 fragmentation can only be done at the original sender,
not by intermediary routers, as if you had the DF bit always set in IPv4.

-- 
Rémi Denis-Courmont
http://www.remlab.net/

"David Madole" wrote:

> I have configured IPv6 on Windows XP SP2 and assigned a global address on my 
> ethernet NIC which is routed to the IPv6 Internet.
> 
> When I try to load a web page in Internet Explorer 7, the page does not 
> load, it just says "Connecting..." and the circle keeps spinning. I get the 
> same thing with Firefox 2.
> 
> However, I can telnet to port 80 on the IPv6 address of the host and 
> manually enter a "GET / HTTP/1.0" and get served the page instantly. So it's 
> not a connectivity issue.
> 
> Sniffing the packets going through my router, I see that the initial TCP 
> handshake is performed, but the browser never sends a request:
> 
> 22:57:52.839389 IP6 (hlim 128, next-header: TCP (6), length: 24) 
> 2001:470:1f07:316::2.1041 > 2001:5c0:0:1::6.80: S, cksum 0xd374 (correct), 
> 2196410878:2196410878(0) win 16384 <mss 1220>
> 22:57:53.077967 IP6 (hlim 117, next-header: TCP (6), length: 24) 
> 2001:5c0:0:1::6.80 > 2001:470:1f07:316::2.1041: S, cksum 0x441e (correct), 
> 2508454117:2508454117(0) ack 2196410879 win 16384 <mss 1440>
> 22:57:53.078280 IP6 (hlim 128, next-header: TCP (6), length: 20) 
> 2001:470:1f07:316::2.1041 > 2001:5c0:0:1::6.80: ., cksum 0x590f (correct), 
> 1:1(0) ack 1 win 17080
> 
> I'm stumped what could be wrong that is affecting both Internet Explorer and 
> Firefox but not telnet to port 80. I have removed anti-virus software for 
> what that's worth.
> 
> Any ideas?
> 
> David
> 

I faced this thing as well. I used NOD32, but it was not able to handle http 
traffic over IPv6. The issue of the removal was working browsers. 

The time to test antivirus software working together with IPv6 has came :)

(The idea of the removal I got while I was reading about corrupted winsock2 
keys at the site http://support.microsoft.com/kb/811259/en-us)

I hope this may helps.

Daniel

> "David Madole" wrote:

>> When I try to load a web page in Internet Explorer 7, the page does not
>> load, it just says "Connecting..." and the circle keeps spinning. I get 
>> the
>> same thing with Firefox 2.
>>
>> However, I can telnet to port 80 on the IPv6 address of the host and
>> manually enter a "GET / HTTP/1.0" and get served the page instantly. So 
>> it's
>> not a connectivity issue.
>>
>> Sniffing the packets going through my router, I see that the initial TCP
>> handshake is performed, but the browser never sends a request:


Same issue here. Firefox and IE not working. TCP tree-way-handshake works 
but not sending out the GET. (captured with tshark)

Opera works fine. Ping works. Telnet works.

My system is XP SP3. IPv6 installed on the machine. Tunnel to 
tunnelbroker.net

Has anyone found a sollution by now?

I'm thinking about installing a VMware machine with XP sp1. Has anyone with 
this issue tryed that allready?

Boonie

"Boonie..." <boonie@invalid.x> schreef in bericht 
news:ev8GLHj1IHA.4004@TK2MSFTNGP03.phx.gbl...
>
>>>
>>> Sniffing the packets going through my router, I see that the initial TCP
>>> handshake is performed, but the browser never sends a request:
>
>
> Same issue here. Firefox and IE not working. TCP tree-way-handshake works 
> but not sending out the GET. (captured with tshark)
>
> Opera works fine. Ping works. Telnet works.

Found another browser. Safari. It also works fine.

That make 2 work and two refuse. Internet Explorer and Firefox are faulty, 
safari and opera work fine.

As this is a microsoft newsgroup and IE is showing this issue I would have 
expected them to respond.

Boonie