RT-N66u problem with IPv6

[ByteKnight]

Hello all,
i have a weird problem:
- with only IPv4 all is working fine (4 wired and 4 wireless clients)
if I enable IPv6 (it doesn't matter IPv6 native or 6to4tunnel), all wireless clients are working fine and with working IPv6 support (checked with ipv6test URls)
BUT: all wired clients cannot connect any more , even the router-IP is not reachable, no DHCP-IP is given. IPv6 and IPv4 stack is enabled (all Windows_7 clients).
I've to disable IPv6 support on the router with my wireless connected laptop, all is working fine, but of course no IPv6 connections possible any more.

Any ideas what is happen here?
Addition:
FW-Version: 3.0.0.4.374.720 or 3.0.0.4.276, even tried some older versions with no difference (it doesn't matter, it occurs with all FW-Version since IPv6 is supported by this router)

 

[wouterv]

It allways helps to know the firmware version of your router.

 

[RogerSC]

This is kind of mysterious, I've been using a dual IPv4/IPv6 dual stack for several months now. With both Asus factory firmware (including .720) and RMerlin firmware versions.

Do you reboot the router after enabling IPv6? I don't see this explaining why you couldn't still connect with IPv4 after enabling IPv6 before rebooting. But rebooting after enabling IPv6 can help the process of getting your IPv6 parameters filled in from your ISP.

The recent RMerlin firmware, like 3.0.0.4.374.32 have an IPv6 log that might be helpful in finding out what's going on (as well as your regular System Log). I'd suggest flashing RMerlin's 3.0.0.4.374.32, doing a factory reset/clear nvram, and manually re-entering your settings, and play with that, paying attention to what goes into your System Log and the IPv6 logs to get some insight into what's going on with your router. Also pay attention to the fact that your System Log will be emptied over a reboot, so you might want to save it on a client computer or USB memory key before rebooting for future reference.

There could be client problems as well, but I would use the router debug tools first to see if you see anything there.

 

[PrivateJoker]

Have you powered off your modem for 5-10 minutes, and also a hardwired client, then turn the modem back on, give it a minute or two, then power up one of your Win7 machines that is connected directly to the modem?

If you do that can you screencap a picture of the NIC adapter status details and share w/ us?

Depending on that outcome, that would at least verify the machine's IPV6 is properly being assigned by the modem and your computer can browse to and use ipv6 test sites online.

 

[RMerlin]

The recent RMerlin firmware, like 3.0.0.4.374.32 have an IPv6 log that might be helpful in finding out what's going on (as well as your regular System Log).

This is actually an Asus feature, they added it in 372 if I remember correctly.

 

[maroy1986]

Sorry for digging out such an old thread but I faced the same issue this week-end trying to enable IPV6 6rd on Videotron (thus I don't think the issue come from Videotron).

I have an ASUS RT-N66U running on stock firmware version 3.0.0.4.376_3861. I actually experienced the same behavior as described above. All my wireless clients were perfectly working, having internet access and whatnot, but all my wired clients couldn't even get their local IP Address. Turning off IPV6 on WAN resolve the issue and make eveything works as usual but then, as said above, I loose all IPV6 benefits.

Have you found any solution since or your issue is still existing when you get IPV6 enable?

 

[wouterv]

My RT-N66U with IPv6 Tunnel 6in4 works perfectly well, I started using IPv6 with firmware 3.0.0.4.374.4561 which adopted Merlins IPv6 firewall.

Did you enable "Enable Router Advertisement"?

 

[maroy1986]

Yes I did "Enable Router Advertisement" option and it doesn't change anything. I didn't made other attempts at enabling IPV6 since this week-end but I'll have a shot at it soon so I'll keep post. The only thing I didn't tried this weekend was a factory reset... Next time I'll try it if I got the same issue. I might have a look to Merlin's builds too

 

[maroy1986]

I just check out the Asus website to check if there was any new firmware available and I found that actually, there's a beta version available. Interesting enough, in the release notes, I found this (in bold underline) :

Bug fixes
- Fixed lease time and lease expires time
- Fixed ethernet connection fail in IPv6 when WAN hwaddr is cloned.
- Fixed allowed and blocked incoming icmp firewall rules.
- Fixed dnsmasq buffer overflow issue.
- Fixed redirect issue when using https only.
- Fixed USB related issues when connected to USB hub.

In fact, you'll guess it, I'm using the "WAN hwaddr" cloned feature... So I guess this is my clue. I think I'm gonna try to upgrade my router to that beta version and see what's going on after that. Or I could just dropped the cloned mac in WAN I guess.

 

[maroy1986]

Quick follow up! I've just upgrade my router to the beta version mentioned above and guess what, everything is now working like a charm! The beta version is 3.0.0.4.378_6117.

Hope it'll help someone else to know that! Thanks.