Problem: No IPv6 when RT-AC66U is in "repeater" mode

[jegesq]

Here's my situation:

I am a TimeWarnerCable subscriber and get my internet through them (300/20 "Ultimate"). I am using a 16x4 channel bonding modem (Arris-Motorola SB6183) and my speeds are excellent, 323+down, 21+ up. IPv6 is working fine with TWC these days.

My cable modem is connected to one of two RT-AC66U's I own which is set up to be in "router" mode, currently running Merlin 374.38_2 (I find that I prefer this over more recent builds...better power/bandwidth, seems to be speedier and I don't use the bells and whistles in the latest builds).

My "router" is located upstairs which gives complete coverage to the second floor bedrooms and a home office located upstairs, and also provides decent coverage to the front portion of our first floor. 5ghz and 2.4ghz are solid and speedy. So that's not an issue.

My second RT-AC66U is located downstairs, and it is set up to operate in "repeater" mode so that it provides a stronger signal to the rear of the house. It is running Merlin Build 374.41. I have it in "repeater" because I cannot get a wired Ethernet connection to the RT-AC66U located downstairs. The repeater itself is connected to a Belkin Gigabit 8 port switch, to which I have connected a Denon receiver, a Blu-Ray player, an HD-DVD player (now obsolete, but we still use it occasionally), a home theater computer (running Win 7), a Toshiba 56" TV (not a smart TV). The "repeater" also broadcasts wireless 5gh and 2.4ghz channels to several wireless devices located in downstairs (an Acer Desktop with both 2.4 and 5ghz adapter) and an HP Officejet Pro 8625 printer that has only 2.4ghz and is connected wirelessly to the "repeater".

Download and upload speeds are really good on all clients, both wired and wireless connected to the "repeater" Those clients connected to the Belkin Gigabit switch downstairs (connected to the "repeater") are getting 280+ down (almost as good as being connected via Ethernet to the upstairs router and/or the cable modem directly). So I'm getting way better speeds than the "halving" that would occur if I was in "bridge" or AP mode with the downstairs unit (and besides, I can't run in AP mode because I cannot get an Ethernet cable to the downstairs RT-AC66U).

Both of the RT-AC66U's have different SSIDs. Upstairs it's "ASUS" and "ASUS 5G" and downstairs it's "ASUS 2nd" and "ASUS 5G 2nd" (mostly so I can determine to which I am connected at any given point, enabling me to tune channels and bands better to reduce/avoid interference from the neighbors).

Here's the issue: IPv6 works just fine on my upstairs "router" (the one functioning as a router). IPv6 however, does not work at all on the "repeater".

All of the devices on the "router" can and do use IPv6. None of the devices on the "repeater" can access IPv6. If I connect a downstairs wireless client to the "repeater" and then check the adapter's properties, it says (in Windows 7/8.1) that IPv6 is not connected. If I then connect the same wireless device to the upstairs "router" wirelessly (on either 5ghz or 2.4 ghz channels), the device will use IPv6. So I know it's not individual device settings that prevents IPv6. It's the "repeater" itself that does not enable IPv6.

I have searched all the SNB forums and other forums on the interwebs, and no one seems to have any answers about how to get IPv6 working on the repeater. Several people asked about it, but no one has suggested an answer. One person posted about two months ago and then concluded that he had wasted too much time on the issue and simply purchased N13AP's.

Any suggestions? Is it possible to get IPv6 working on an Asus RT-AC66U when running in "repeater" mode?

Any and all help greatly appreciated.

 

[PabloAbonia]

IPV6 is probably not turned on at all in repeater mode. I have a similar setup, but I am using my second device rt-ac68u as an wired access point. There is no IPV6 tab, and it doesn't get any IPV6 address for itself. My wireless devices are able to get an address from the non-wifi router rt-ac56u.

That might work for you if you use a powerline adapter to provide a wired connection to your current repeater setup, and then switch to access point mode. These adapters get upto 0.5 gigabit and have worked well for me. Mine are a 500av device from netgear.

The only device which would be impacted by speed is the computer, but I have xbox360 running windows media center off the powerline with no problems at 1080p resolution.

For a real solution to the IPv6 problem as the access point will not get its own IPv6 address I have file a report with asus so that they at least provide a link-local address for AP mode.

Pablo


Pablo

 

[jegesq]

Pablo:

Thanks for the response. I've tried to use Powerline previously. I ran it using Belkin adapters (I think they were older 300 units) from the router upstairs to the downstairs RT-AC66U set as an AP, and my speeds were dramatically lower than what I now get when using the AC66U as a "repeater". Maybe it's the way my house is wired, or that my electrical lines are noisy, I am not sure, but it's a lot slower using Powerline. My speeds with the repeater are terrific and I can stream in 1080p without any issues at all, no stutter, no delays, picture-perfect. I have the HTPC running Win7 Media Center connected via Ethernet to the repeater, and the PC's video and audio output run through my Denon receiver and to the 56" Toshiba) and I get 260+Mbps download regularly with the repeater. The repeater is rock-solid in that respect. It just doesn't get IPv6.

Admitttedly the clients that are connected wirelessly to the repeater seem to have the speed cut in half issue, but even so, they are running well over 100Mbps download, and everything, whether wired or wireless gets 21+Mbps upload. So there's really no latency, stutter or undue delays on any device connected to the repeater, and with it, I get excellent coverage everywhere in the rear portion of our house and out in the backyard and pool area. Just no IPv6.

What's weird is that I ran some additional tests and it seems that if I do an "ipconfig/all" from a command prompt, regardless of whether I'm connected to the router or the repeater, whether wired or wireless, I get the same info, which shows that I have IPv6 link-local info, temporary preferred IPv6 and DUID IPv6 DHCP6 addresses.

And yet checking the "status" of an adapter when connected to the router shows "Internet Connectivity" for IPv6, and "No Internet Activity" when connected to the repeater. And just to nail it down, when doing a "What is My IP" in Google, if I'm connected to the router, I get an IPv6 public address, and if connected to the repeater, I get an IPv4 address only.

So yes, the repeater does not appear to actually utilize IPv6 for DNS.

Is this a setting in the repeater? Is it an issue with how routing is performed when repeating a routed wireless signal? Would the result be different if using a different firmware for the repeater?

I'm thinking of trying MOCA, but that's going to cost and MOCA adapters are hard to find. But as things are now, it doesn't seem to affect anything adversely, it's just annoying that the repeater doesn't seem to pass IPv6 through.

Any other suggestions or help would be greatly appreciated. Also interested to learn what ASUS says. Thanks Pablo.

 

[PabloAbonia]

Bear in mind I think that most of the devices you've mentioned probably don't make use of IPv6.

For it to work with the computer I had to enable both router advertisement and the dhcp6 server for the mix of devices I had. Unfortunately native IPv6 with TWC is too unreliable, so I am using a tunnel for it which has been solid for me.

That might work for you.

Nothing new from asus, although it seems to me that they are not paying as much attention to the non-router modes of operation.



Pablo

 

[PabloAbonia]

Also there is no IPv6 setting for the access point and I suspect that it is not in the repeater mode either,


Pablo

 

[jegesq]

Pablo,

Not sure what you mean when you say "most of the devices you've mentioned probably don't make use of IPv6." All of the devices I've mentioned, which consist of two desktop computers (running Windows 8.1), a laptop running 8.1, and an HTPC running Windows 7, all make use of IPv6. The Denon receiver doesn't (as far as I know) and neither does the Toshiba or the BluRay or HD-DVD player. But those are only rarely used peripherals that don't NEED internet access, but occasionally make use of internet access (and when I say "rarely" I mean rarely, if ever). I mentioned those devices not because I was trying to figure out why or how to implement IPv6 with them, but simply to point out some of the devices that are using the "repeater" located downstairs in our home that are connected to the repeater. I probably shouldn't have even mentioned them because they are irrelevant to the issue I was bringing up.

I will take you word for the AP settings menu. I know that the only thing the "repeater" menu does is allow you to set the channel that is being "repeated" (2.4 or 5.0), and then you can rebroadcast it using both the 2.4 and 5.0 radios in the repeater unit. The settings for "repeater" are pretty minimal, in keeping with the function of a repeater, and there's no way to enable or disable IPv6 in the repeater GUI.

Tunneling is a sort of kludgy solution to implementing IPv6 (for many reasons that are beside the point here, but if you're interested, take a look at the Wikipedia article on IPv6), and I do not see how using a tunnel on the router (which is where the IPv6 DHCP routing is happening) would change anything with the repeater itself.To be clear, my upstairs router has absolutely no issues with implementing and using IPv6 from TWC, and I've found that whatever issues may have previously existed with TWC's IPv6 implementation have been fixed and it's working fine, at least at my location.

I will contact ASUS support as well to see if they have any insights on the issue of why IPv6 is apparently not being passed through when repeating the router's wireless signal. Maybe it's just not possible to accomplish, or maybe it's just an issue with the firmware or some missing control that could be implemented in the GUI.

One thing is certain though and that is that IPv6 isn't being passed through from or to clients attached to a unit that is operating as a repeater.

 

[PabloAbonia]

In my case, in spite of IPv6 not being available in AP mode, all of my devices still get it, inclusive of those on the AP. This only occurred with a tunnel on my router and pointed to a problem with native IPv6 which is still unreliable for me.

I thought of this when you mentioned what was showing up in your ipconfig which would often happen to my native rather than tunnel link configuration. I'm only using the tunnel to have iipv6 work reliably in the current setup of IPv6 on asus.

I'm using 47 now, and am waiting a bit before moving to 48.



Pablo

 

[jegesq]

Pablo,

I suppose my reluctance with IPv6 tunnels primarily pertains to security issues: As you probably know, one of the main benefits of IPv6 is that it gives a device using it a publicly accessible address (e.g., so one can communicate with a connected device remotely, i.e., think "internet of things"). The problem with this, and with most tunneling implementations is when using a tunnel, you have a network running IPv6 traffic that can't be seen because it is disguised as IPv4 traffic (this is the principle behind tunneling, i.e., it allows IPv6 traffic to be carried on the IPv4 backbone, and thus it looks like IPv4 data). This in turn exposes one's network to potential IPv6-based attacks such as botnet command and control. So whatever tunnel you're implementing it's extremely important to have specific IPv6-aware firewalls, intrusion-detection systems and network management tools in order to have visibility into encapsulated IPv6 packets. This is something that should cause most home network users at least some degree of concern, particularly if they are keeping and exchanging private financial information or other confidential data across their home networks. It probably doesn't matter for streaming video files, but it does expose weaknesses in connected devices to intrusion and data theft (including password theft). And it's why using native IPv6 implemented through a router with a good firewall and data intrusion protection is a much better way to use IPv6 rather than using a tunnel, at least in my highly under-informed opinion about IPv6 based on what I've read.

I don't know that you've experienced any of these negatives by using tunneling, but to me, it just seems like more work than it's worth to implement particularly given the potential risks when run through a tunnel.

I've thought about trying out different firmwares on my repeater (since I know that the router is getting and using native IPv6 just fine), but I don't think I want to spend that much time on this. After all, if the ASUS repeater is truly repeating, it should be able to forward native IPv6 without too much user intervention, and that's why I'm going to address this issue directly to ASUS product support.

 

[PabloAbonia]

I understand, but for me IPv6 is not working natively so my choices are limited. Also, there is an IPv6 compliant firewall on the router itself, and I do perform checks on the firewall itself. There is also the randomization of IPv6 addresses that most current os are using, the so-called temporary address.

My main interest in IPv6 is the elimination of nat, and supposed performance improvements.

All the same problems you noted can occur with ipv4.

I totally understand not wanting to use a tunnel.


Pablo