Win7 IPv6 Connectivity: No Internet Access

[ratcheer]

This is in followup to the problem I was asking about in another thread. My tunnel endpoint is a router running DD-wrt. The router advertises the IPv6 to the LAN using radvd. My Linux client PC uses the HE tunnel on a daily basis with no trouble at all. But the Win7 client, which used to work, stopped working. I can find many, many complaints of the exact same problem all over the internet, but no real solution.

http://www.tunnelbroker.net/forums/index.php?topic=1641.0

Here is my ipconfig /all

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Windows IP Configuration

  Host Name . . . . . . . . . . . . : IanCuthbertson
  Primary Dns Suffix  . . . . . . . :
  Node Type . . . . . . . . . . . . : Hybrid
  IP Routing Enabled. . . . . . . . : No
  WINS Proxy Enabled. . . . . . . . : No

Ethernet adapter Local Area Connection:

  Connection-specific DNS Suffix  . :
  Description . . . . . . . . . . . : Realtek RTL8168C(P)/8111C(P) Family PCI-E
Gigabit Ethernet NIC (NDIS 6.20)
  Physical Address. . . . . . . . . : 00-23-54-76-59-36
  DHCP Enabled. . . . . . . . . . . : Yes
  Autoconfiguration Enabled . . . . : Yes
  IPv6 Address. . . . . . . . . . . : 2001:470:8:b57:223:54ff:fe76:5936(Depreca
ted)
  Link-local IPv6 Address . . . . . : fe80::223:54ff:fe76:5936%10(Preferred)
  IPv4 Address. . . . . . . . . . . : 192.168.1.100(Preferred)
  Subnet Mask . . . . . . . . . . . : 255.255.255.0
  Lease Obtained. . . . . . . . . . : Wednesday, March 30, 2011 11:42:05 AM
  Lease Expires . . . . . . . . . . : Friday, April 08, 2011 9:39:00 AM
  Default Gateway . . . . . . . . . : fe80::222:3fff:fe1a:f525%10
                                      192.168.1.1
  DHCP Server . . . . . . . . . . . : 192.168.1.1
  DNS Servers . . . . . . . . . . . : 192.168.1.1
  NetBIOS over Tcpip. . . . . . . . : Enabled

Here is route print

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===========================================================================
Interface List
10...00 23 54 76 59 36 ......Realtek RTL8168C(P)/8111C(P) Family PCI-E Gigabit
Ethernet NIC (NDIS 6.20)
 1...........................Software Loopback Interface 1
===========================================================================

IPv4 Route Table
===========================================================================
Active Routes:
Network Destination        Netmask          Gateway       Interface  Metric
         0.0.0.0          0.0.0.0      192.168.1.1    192.168.1.100     20
       127.0.0.0        255.0.0.0         On-link         127.0.0.1    306
       127.0.0.1  255.255.255.255         On-link         127.0.0.1    306
 127.255.255.255  255.255.255.255         On-link         127.0.0.1    306
     192.168.1.0    255.255.255.0         On-link     192.168.1.100    276
   192.168.1.100  255.255.255.255         On-link     192.168.1.100    276
   192.168.1.255  255.255.255.255         On-link     192.168.1.100    276
       224.0.0.0        240.0.0.0         On-link         127.0.0.1    306
       224.0.0.0        240.0.0.0         On-link     192.168.1.100    276
 255.255.255.255  255.255.255.255         On-link         127.0.0.1    306
 255.255.255.255  255.255.255.255         On-link     192.168.1.100    276
===========================================================================
Persistent Routes:
 None

IPv6 Route Table
===========================================================================
Active Routes:
If Metric Network Destination      Gateway
10    276 ::/0                     fe80::222:3fff:fe1a:f525
 1    306 ::1/128                  On-link
10     28 2001:470:8:b57::/64      On-link
10    276 2001:470:8:b57:223:54ff:fe76:5936/128
                                   On-link
10    276 fe80::/64                On-link
10    276 fe80::223:54ff:fe76:5936/128
                                   On-link
 1    306 ff00::/8                 On-link
10    276 ff00::/8                 On-link
===========================================================================
Persistent Routes:
 None

Here is netsh interface ipv6 dump

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#========================
# Interface configuration
#========================
pushd interface


popd
# End of interface configuration



# ----------------------------------
# IPHTTPS Configuration
# ----------------------------------
pushd interface httpstunnel

reset


popd
# End of IPHTTPS configuration



# ----------------------------------
# IPv4 Configuration
# ----------------------------------
pushd interface ipv4

reset
set global icmpredirects=enabled


popd
# End of IPv4 configuration



# ----------------------------------
# IPv6 Configuration
# ----------------------------------
pushd interface ipv6

reset
set global randomizeidentifiers=disabled
set privacy state=disabled


popd
# End of IPv6 configuration



# ----------------------------------
# ISATAP Configuration
# ----------------------------------
pushd interface isatap
set state disabled



popd
# End of ISATAP configuration



# ----------------------------------
# 6to4 Configuration
# ----------------------------------
pushd interface 6to4

reset



popd
# End of 6to4 configuration



# ----------------------------------
# ISATAP Configuration
# ----------------------------------
pushd interface isatap
set state disabled



popd
# End of ISATAP configuration


#========================
# Port Proxy configuration
#========================
pushd interface portproxy

reset


popd

# End of Port Proxy configuration



# ----------------------------------
# TCP Configuration
# ----------------------------------
pushd interface tcp

reset

set global rss=enabled chimney=automatic autotuninglevel=normal congestionprovid
er=none ecncapability=disabled timestamps=disabled netdma=enabled dca=enabled


popd
# End of TCP configuration



# ----------------------------------
# Teredo Configuration
# ----------------------------------
pushd interface teredo
set state type=disabled servername=teredo.ipv6.microsoft.com. servervirtualip=0.
0.0.0



popd
# End of Teredo configuration



# ----------------------------------
# 6to4 Configuration
# ----------------------------------
pushd interface 6to4

reset



popd
# End of 6to4 configuration


netsh interface>ipv6
netsh interface ipv6>dump


# ----------------------------------
# IPv6 Configuration
# ----------------------------------
pushd interface ipv6

reset
set global randomizeidentifiers=disabled
set privacy state=disabled


popd
# End of IPv6 configuration



# ----------------------------------
# ISATAP Configuration
# ----------------------------------
pushd interface isatap
set state disabled



popd
# End of ISATAP configuration



# ----------------------------------
# 6to4 Configuration
# ----------------------------------
pushd interface 6to4

reset



popd
# End of 6to4 configuration

Does anyone know how to get it going, again?

Thanks, Tim

[cholzhauer]

It almost looks like a reboot would fix this.

Your IPv6 address for your wired connection is deprecated. A reboot should bring it back

Is your address static or assigned via RA?

I assume  fe80::222:3fff:fe1a:f525 is the address of your DDWRT router?

[ratcheer]

Ok, I will try rebooting, now. But, the machine has been rebooted several times in the past week or so and the problem continues.

I'll be back in a few minutes. Thanks,

Tim

[ratcheer]

Ok, reboot fixed it for now. Here is what ipv6.he.net shows:

Your IP address is: 2001:470:8:b57:223:54ff:fe76:5936

Any idea why it loses connectivity?

Thanks,
Tim

[cholzhauer]

No, unfortunately I don't.

I'd be curious to see how long it takes to "Break" (if it does again)

Is your address static or assigned via RA?

[ratcheer]

Is your address static or assigned via RA?

Which address, the IPv6 client address of the Win7 PC? That is assigned by the RA, I guess (Router Advertisement?). Note that I said the Win7 client did have an IPv6 address even when the connectivity was broken. This should be shown in the ipconfig output of the top post.

Tim

[cholzhauer]

Yeah, I meant the address of your win7 machine.

I'd be curious to see if this breaks again, if you statically set that address and see if it re-breaks

There was an address in your first post, but it was deprecated, so it wasn't being used.

[ratcheer]

Yeah, I meant the address of your win7 machine.

I'd be curious to see if this breaks again, if you statically set that address and see if it re-breaks

There was an address in your first post, but it was deprecated, so it wasn't being used.

Oh, yes. Maybe kind of like a DHCP lease expiring?

Anyway, what command would set a static IPv6 address in Win7? Or, would I just copy the address it is using now into the IPv6 Properties dialog?

Tim

[cholzhauer]

The easiest way is just to add it to the IPv6 properties dialog box.

IP address can be any address in your routed /64

gateway is your router

DNS is either your local DNS server or the HE DNS server... or leave it blank to use IPv4 DNS

[ratcheer]

Thanks. I tried it several times yesterday afternoon and evening and it kept working, but this morning it was deprecated, again.

I'm trying the static IP method, but I don't understand why it should be necessary. Since this doesn't happen to my Linux client, I don't believe it has anything to do with the router. I think it is something about Win7.

More, later...

Tim

[ratcheer]

Ok, I set the static IPv6 address, IPv6 gateway, and prefix length. I left the DNS servers empty because I am not sure what to put. It is working again, but since I had to reboot for the changes to take effect, it will take some time before I will know if it stops deprecating the address.

I am still annoyed at having to do this, even if it does work. I am still going to do more research on the problem.

Thanks very much for your help. I am learning more and more about using IPv6 almost every day.

Tim

[cholzhauer]

There was a thread regarding this on the IPv6 mailing list yesterday...here's a copy of the original email

Hi,

A number of our customers are having trouble with IPv6 under Windows Vista and 7 on our IPv6 trial.

Currently we are giving customers a static delegated prefix via DHCPv6-PD (a /60 currently). When they have an ADSL drop out, some IPv6 CPE is deprecating the assigned LAN interface global /64 prefix by sending an RA with a zero second preferred lifetime for the prefix.
Windows Vista and 7 are quite correctly labelling the prefix as deprecated, as it still has a non-zero valid lifetime. Deprecating the prefix at this time makes sense as there is a possibility that the delegated prefix may not be re-assigned to the CPE after the ADSL link is restored, and may be re-assigned by the ISP to another customer. This is also the behavior specified in the recently published RFC6204, "Basic Requirements for IPv6 Customer Edge Routers".

When the ADSL link comes up again, and the CPE re-acquires the same delegated prefix, it re-announces the same /64 onto the LAN with a non-zero preferred lifetime. Windows Vista and 7 receive and update the non-zero prefix lifetimes for the addresses, but do not change the addresses back to preferred. Windows XP does, as do other operating systems. Windows Vista and 7 not setting the addresses back to preferred seems to then cause IPv6 connectivity to then fail, causing Vista and 7 to revert back to using IPv4 only. Windows Vista and 7 have no trouble at this time with new prefixes, so the issue seems to be specifically related to changing a previously deprecated prefix back to a preferred one.

Does anybody know how I can report this bug with Microsoft on behalf of our customers?

(If anybody wants to have a go reproducing this, the latest CVS version of radvd now has a "DeprecatePrefix" option for prefixes. To view the
IPv6 address status and lifetimes under Windows, use the "netsh interface ipv6 show address" "cmd" command.)

Thanks,
Mark.

So it seems like it's not just you...I've never had any problems though, but it seems like I"m in the minority.

Are you running SP1?

[ratcheer]

Thanks for the info. Yes, I installed SP1 about two weeks ago.

Tim

[ratcheer]

Static assignment does not help. After waiting overnight, the IPv6 assignment is deprecated, anyway.

In one of my searches, I found a tip on recovering the assignment "on the fly". I am not at the PC where I bookmarked it, but it was using netsh commands to disable admin on the Lan Connection, then enable it again. I will test this later, when I can get to the other PC.

Tim

[ratcheer]

Static assignment does not help. After waiting overnight, the IPv6 assignment is deprecated, anyway.

In one of my searches, I found a tip on recovering the assignment "on the fly". I am not at the PC where I bookmarked it, but it was using netsh commands to disable admin on the Lan Connection, then enable it again. I will test this later, when I can get to the other PC.

Tim

Ok, I found the commands and they do reset the IPv6 address assignment to Preferred:

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netsh interface set interface name="Local Area Connection" admin=disabled
netsh interface set interface name="Local Area Connection" admin=enabled



Tim