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


smyers119 wrote:
There is no "sub-options" under hwnat. You can enable or disable. That's it.

There's this. Not IPv6 "routing", but "forwarding".

 

2.png3.png

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

Right, those settings are not "under" hwnat (system-offload-hwnat). they are under system-offload-ipv6. Those settings don't apply to the ERX and are not supported by it. ERX uses hwnat and ipsec offloading. ERL/ERPOE use IPv4/IPv6 options but not hwnat. If you try to use one of the IPv4/v6 options on the ERX it just gives an error.

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

those settings only apply to the cavium based routers, the er-x has a mediatek chip

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

If only I'd read the reference manual.

 

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

Any updates on this? I lose ipv6 with hwnat enabled on comcast. Just curious if anyone has a mod yet?

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

[ Edited ]

I can confirm this is a problem. I'm ripping out a USG at my home temporarily to troubleshoot, which I replaced with an ERX. Sure enough hwnat on no IPv6. hwnat off IPv6 works.

 

1.9.7HF4

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

I had to replace the entire device. I can't go without IPv6. Sold it on craigslist for near purchase price.

 

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

[ Edited ]

Interesting (well maybe).

 

I replaced my DHCPv6 WAN config with a backup I had from my EdgeRouter POE, which I did manually and was not generated by the wizard (because the wizard didn't exist then). I also enabled hwnat offload. Not sure if it will stick and is just something temporary from the existing lease when I had offload off, but post-reboot it's working. I even rebooted the modem and the ERX a second time and I still have IPv6 connectivity on both LAN and WAN.

 

This is (formerly TWC) Spectrum service in Los Angeles. I'll add that with the previous wizard config and hwnat enabled my WAN wouldn't even get an IPv6 address. 

 

Before: 

interfaces {
    ethernet eth0 {
        address dhcp
        description Spectrum
        dhcpv6-pd {
            pd 0 {
                interface switch0 {
                    host-address ::1
                    service slaac
                }
                prefix-length /64
            }
            rapid-commit enable
        }

After - removing service slaac, host-address and changing /64 to 64: 

interfaces {
    ethernet eth0 {
        address dhcp
        description Spectrum
        dhcpv6-pd {
            pd 0 {
                interface switch0 {
                }
                prefix-length 64
            }
            rapid-commit enable
        }

My switch0 section: 

 switch switch0 {
     address 192.168.192.1/24
     description Local
     ipv6 {
         dup-addr-detect-transmits 1
         router-advert {
             cur-hop-limit 64
             link-mtu 0
             managed-flag false
             max-interval 600
             other-config-flag false
             prefix ::/64 {
                 autonomous-flag true
                 on-link-flag true
                 valid-lifetime 2592000
             }
             reachable-time 0
             retrans-timer 0
             send-advert true
         }
     }

IPv6 commands for both WAN and LAN... assuming eth0 WAN and switch0 LAN. Note these command do not include the VERY IMPORTANT firewall portions.

 

** WAN ** eth0
set interfaces ethernet eth0 dhcpv6-pd pd 0 interface switch0 set interfaces ethernet eth0 dhcpv6-pd pd 0 prefix-length 64 set interfaces ethernet eth0 dhcpv6-pd rapid-commit enable
** LAN ** switch0 set interfaces switch switch0 ipv6 dup-addr-detect-transmits 1 set interfaces switch switch0 ipv6 router-advert cur-hop-limit 64 set interfaces switch switch0 ipv6 router-advert link-mtu 0 set interfaces switch switch0 ipv6 router-advert managed-flag false set interfaces switch switch0 ipv6 router-advert max-interval 600 set interfaces switch switch0 ipv6 router-advert other-config-flag false set interfaces switch switch0 ipv6 router-advert prefix '::/64' autonomous-flag true set interfaces switch switch0 ipv6 router-advert prefix '::/64' on-link-flag true set interfaces switch switch0 ipv6 router-advert prefix '::/64' valid-lifetime 2592000 set interfaces switch switch0 ipv6 router-advert reachable-time 0 set interfaces switch switch0 ipv6 router-advert retrans-timer 0 set interfaces switch switch0 ipv6 router-advert send-advert true

Anyone care to test this? 

 

I have a feeling it's a fluke and it won't last... I'll update everyone tomorrow.

 

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

[ Edited ]

has anyone looked into the DHCP advertisement with hop limit 0 thing any more? i know it was mentioned earlier in the thread. found this on dslreports

 

https://www.dslreports.com/forum/r31666417-IPv6-IPv6-DHCP-Advertisement-with-hop-limit-of-0

 

my area has a cisco CMTS so that could explain why my ipv6 with hwnat works fine

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

IPv6 connectivity fell off today with hwnat enabled. So the config change I detailed previously didn't help long term.

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

I also have the issue with the ERX where hardware offloading breaks ipv6.  With offloading off the ipv6 works.

 

The cable modem I have it connected to is a Motorola SB6121

 

I hope a fix is found for this issue soon, I require IPV6, and I have a high speed connection that is bottlenecked by offloading being off.

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

I no longer have a vested interested in seeing this resolved as my solution was to stop using the ER-X. I do still check in on this thread every so often as I have two in storage that some day could be put back in use on the off chance that there is every a resolution.

 

From the lack of participation in this thread from Ubiquity I think it's pretty clear they aren't much interested in figuring out this problem and the chance of a resolution from them is slim. Here's a thought Ubiquity, just discontinue the ER-X product line and offer a trade in discount to folks that are having this issue on one of your other products that do work.

 

Sorry if I come off as snotty. I just feel like sometimes this company is run by some guy and his buddy out of his garage rather than than being the multinational corporation that it is. This problem has been occuring for almost a year now, and if this were Cisco or Brocade/Broadcom it would have been solved long ago. Man Frustrated

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

In fairness to the good folks at Ubiiquiti, I would refer you to @ooferomen's post a few back. This issue is not confined to Ubiquiti routers (it's been reported on Cisco and TP-Link routers as well) nor to Comcast (Time-Warner/Spectrum users and maybe others have also reported it). It is almost certainly due to different equipment following different standards being used in different cable office head-ends, perhaps in combination with the Linux network stacks in use on the routers. Not an easy nut to crack if you don't happen to be downstream from one of those head-ends exposing the problem (and most of us are not).

 

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

[ Edited ]

This issue is not confined to Ubiquiti routers (it's been reported on Cisco and TP-Link routers as well)


That doesn't make it better. Just because Cisco and TP-Link also have similar issues doesn't suddenly make this acceptable.

 


nor to Comcast (Time-Warner/Spectrum users and maybe others have also reported it)


That only make it worse as it means it affects even more people.

 

As for this not being an easy nut to crack. Im sure if they asked there would be plenty of people willing to let a UBNT employee come over and play with their network, or allow them remote access to their router for testing purposes, or install whatever debugging device they may need in order to track this down. As far as I can tell they have not really taken this step and are instead quiet on the issue now.

 

If I had to guess, and I admit it really is a guess, UBNT is aware of the issue, probably have a decent understanding of what the issue is, but have no mechanism to actually fix it. Thats the best case scenario for us, because the alternative is they really just don't care enough to prioritize it.

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

I have a strong suspicion the issue is actually baked into the hardware, and it's unfixable without replacing hardware. 

 

Given that hardware offload works on ipv4 just fine, and no-offload works just fine on ipv6 just fine, it wouldn't make sense to do a recall of every single er-x ever made just to fix the issue if that is the case.

A better solution would be to implement fastpath, which gets hwnat-like speeds, with cpu, bypassing the problem entirely.

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

I’m actually a DOCSIS/CMTS engineer. There’s actually a couple different relay modes out there for ARRIS/Cisco CMTSes when it comes to prefix delegation. I’d like some folks who previously have and have not had issues to post the following info for me:

1. Working or not working with hwnat offload? Please post pcap.
2. Have you tried enabling DHCPv6 on your WAN interface for address assignment to the WAN (not prefix delegation to LAN) and does it work? Please post pcap.
3. Can you post the MAC address of your IPv4 default gateway?
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Re: Comcast IPv6 issues when hwnat enabled on ER-X

Another datapoint from a customer of the other Co* ISP... On Cox, new to Gigablast (of the DOCSIS 3.1 variety), I have a Motorola MB8600 modem and was getting 450 Mbps down with hwnat off, but IPv6 was working. Turned on hwnat and speed jumped up but IPv6 is dead (though the router itself has an IPv6 address). Would be nice to have both working properly...

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

Perhaps a long shot, but has anyone tried v1.10 beta to see if this is still a problem with this version?  Didn't see anything in the change log that gave me hope, but was thinking of taking the plunge and crossing my fingers....

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

On 1.10 Beta (and was on Alpha). No change, problem still exists with offload enabled.

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

I don't think ubiquity is going to patch this, since it's a hardware problem...

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