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Re: Comcast IPv6 issues when hwnat enabled on ER-X

What would be helpful is showing the effects of both states. The working and non working states. 

 

Also if you're using Windows:

 

 

netsh interface ipv6 show neighbors

 

 

You might want to take a look at the routing table for the device having problems. Keep in mind on the neighbor table there should be a LL address that belong to Comcast, you should be able to ping the address as well with no problems.

 

If you suspect MTU issues, use ping to check the endpoints.

New Member
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Re: Comcast IPv6 issues when hwnat enabled on ER-X

I assume that was meant for people who ARE having problems with hwnat. As previously explained, we are not. A comparison of our results with hwnat enabled and those from someone actually seeing a problem might be helpful to the ubnt engineers.

-Tom
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Re: Comcast IPv6 issues when hwnat enabled on ER-X

[ Edited ]

To clarify my prevous comment:

 

I tried your exact config and no dice for me. It must be either my modem (sb-6183) or Comcast issue and

the er-x works fine with no hwnat (ipv4 and ipv6)  as does my RB750GR3 (which isn't using hwnat - just a

different method to accomplish something similiar).

 

Thanks for your help. I appreciate it.

 

 

Fred

 

 

 

 

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Re: Comcast IPv6 issues when hwnat enabled on ER-X

I'd like to just report in that I'm using ER-X with a motorolla surfboard 6141 modem, with hwnat *off*, and it's working ipv6 just fine.

Probably not useful, but an anecdote none the less.

New Member
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Re: Comcast IPv6 issues when hwnat enabled on ER-X

I also have a SB-6141, I could test this out later in the week with the ER-X.

 

Another thing might want to keep in mind is that Comcast-wise the equipment behind your cable modem varies per location. This could cause problems with reproducing issues.

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Re: Comcast IPv6 issues when hwnat enabled on ER-X

It varies a lot actually.

https://mydeviceinfo.xfinity.com/customerinfo

There is a rather long list of possible modems.

New Member
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Re: Comcast IPv6 issues when hwnat enabled on ER-X

Here's what I see so far. Apparently, most ER-X users are working just fine on Comcast with hwnat enabled. Some, however, are having problems, apparently with LAN clients not getting (or losing) an IPv6 address. It
might help the ubnt folks if we had a little data from those NON-working systems.

Here are some of the differences we know of between "it works" and "it doesn't".

1) Geography. As @unknownzer pointed out, the upstream equipment at Comcast
   in different geographies may vary, and there could be an interoperability
   problem there. If so, you might expect the problem systems to be clustered.

   An unexpected DHCP source port number was mentioned in an earlier thread,

   for example.

2) Modems. There are reports of both problems and no problems with the SB6183.
   We have had no apparent problem with hwnat enabled on both an SB6121 and an
   SB6183. It's unclear whether anyone IS having a problem with hwnat enabled
   on an SB6121 or SB6141 (or any other modem).

3) config.boot. @fibroce had problems using the same config.boot we use, and
   we have not had problems. We have also both used the SB6183 with that
   config.boot. See #1.

4) Other.
     - Neighbor count or churn? No data.
     - Comcast service tier? Little, if any, data.

I'd be curious to know from the ubnt folks how hwnat COULD interfere with IPv6
(or, maybe more specifically, DHCPv6).

New Member
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Re: Comcast IPv6 issues when hwnat enabled on ER-X

1) I am in Johns Creek, GA (North metro Atlanta)

2) SB6183

3) Running a slighty modified version of the one Steve Jenkins posted (on github) and here. Just

   deleted the second network and changed the IP addresses. Works great with no hwnat.

   https://github.com/stevejenkins/UBNT-EdgeRouter-Example-Configs

4) On 300/30 Comcast residental tier. I get 361mb/s / 30 mb on speedtest.net. (using RB750GR3

    neighbors - no data as I am not using er-x at moment. I can add that later.

 

Fred

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Re: Comcast IPv6 issues when hwnat enabled on ER-X

As another reference point, I just updated my EdgeRouter X with the 1.9.7-alpha3 FW. I have hwnat enabled on a Comcast residential network in the Seattle, WA area. DHCPv6 seems to be working fine.

This is where I used to list my UBNT gear, but now it's mostly stuff I'm not allowed to talk about yet. Man Wink
942.22 Mbps down / 926.27 Mbps up (http://result.googlefiber.net/share/316298352.png)
My Blog: http://www.stevejenkins.com/
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Re: Comcast IPv6 issues when hwnat enabled on ER-X

Steve must be using a different modem to get 1gb. The sb6183 is only 

capable of around 430mb.

 

I loaded the 1.9.7 alpha3 firmware and still no ipv6 with hwnat enabled.

 

Fred

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Re: Comcast IPv6 issues when hwnat enabled on ER-X

I tried enabling hwnat on 1.9.1.1, and my ipv6 stayed, though I do have SmartQoS enabled, which would disable hwnat for wan traffic.

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Re: Comcast IPv6 issues when hwnat enabled on ER-X

Correction, after some time, the ipv6 address went away
New Member
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Re: Comcast IPv6 issues when hwnat enabled on ER-X

If you change it without rebooting, it will work for a while and then go away when the lease expires.

 

 

Emerging Member
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Re: Comcast IPv6 issues when hwnat enabled on ER-X

i have swiched to a sb6183 and ipv6 still works fine, you can rule that one out i guess

New Member
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Re: Comcast IPv6 issues when hwnat enabled on ER-X

Thanks.

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Re: Comcast IPv6 issues when hwnat enabled on ER-X

Unfortunately another "me too".

 

I'm running on Comcast with a SB6141 modem.

 

When I turn on hwnat I can't get an IPv6 address on boot.

 

Turning this off fixes it.

New Member
Posts: 6
Registered: ‎05-12-2017

Re: Comcast IPv6 issues when hwnat enabled on ER-X

I gave up on the ER-X and moved to a pfSense router instead, been working great. ER-X still works as a nice switch.

New Member
Posts: 11
Registered: ‎06-13-2017

Re: Comcast IPv6 issues when hwnat enabled on ER-X

I have not had issues with losing ipv6 on comcast but i do use a Zoom modem 5341J instead of the comcast modem....

I will keep a closer eye on it though.

New Member
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Re: Comcast IPv6 issues when hwnat enabled on ER-X

This doesn’t appear to be just a Comcast issue.   I have a second location which is in Charter in the St. Louis area and the config is the same other than Charter gives a /56 PD and Comcast gives a /64.   In both cases it stops working when HWNAT is enabled and the DHCPv6 traffic is being silently dropped (or ignored) by the ERX.  The cable modems are different in both cases as well.  An Arris 6190 in the Comcast case and an Arris TM1602 in the Charter case.

New Member
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Re: Comcast IPv6 issues when hwnat enabled on ER-X

I have not experimented in the last week or so but Comcast ipv6 works fine with my rb-750gr3.

I still believe there is a solution for the ER-X and hwnat. I will continue the search.

 

Thanks,

 

Fred

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