Intermittent ipv6 connectivity after upgrading to fiber in North Vancouver

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RR923
Connector

I just upgraded to fiber from DSL and got swapped to a T3200m modem as well. I am still getting an ipv6 address (real 2001:569:...)however, routing of ipv6 is no longer working. Windows responds "Destination net unreachable" when trying to ping any valid ipv6 address. I am able to ping the link local and ipv6 address of the T3200m. On the T3200m, using the ipv6 ping test page, all internet addresses are timing out as well which leads me to believe there's an issue in the core network. I've rebooted both the ONT (Nokia) and T3200m but the same problem persists.

 

Ipv6 was working fine on DSL, and it has intermittently worked in the 36 hours or so that I've had fiber but it seems more down than up. Is anyone else experiencing this issue? Any next troubleshooting steps?

RR923
Connector

Further update:

 

1. IPv6 works upon initial reboot of the T3200m router. I am able to ping external ipv6 addresses

2. It seems exactly 92 minutes after reboot, the T3200m stops routing ipv6 but continues to route ipv4.

 

Telus, Any ideas? I cannot be rebooting the router every 90 minutes. I have a case with Technical support, but their answer is that they are not trained on ipv6.

RR923
Connector

After some further troubleshooting:

 

In the T3200m ipv6 routing table, the default route (to the link local address of the Telus edge router) disappears after 90 minutes leaving no default route for ipv6 traffic. This is exactly the T2 timer specified in the DHCPv6 lease from the Telus edge router. Analysis of the DHCPv6 packets between the T3200m and the Telus edge router show that the T3200m requests and the Telus DHCP server does renew the v6 PD lease at ~60 minutes but it seems the Actiontec does not process this renewal and removes the ipv6 default route incorrectly when the original T2 value from the initial lease expires. This appears to be a very serious Actiontec bug. I'm on version 31.164L.13. Is this a known issue?

 

This is easily reproduceable - after a router restart, ipv6 works for the first 90 minutes and then stops routing. ipv6 websites (google, netflix, etc) become sluggish as they need to fallback to ipv4.

RR923
Connector

I need to update my original analysis. The default route in ipv6 is provided by ICMP RA (Router Advertisement) messages not DHCPv6. From my packet capture, it appears that the Telus edge router is only sending RAs as a response to a Router Solicit, not at regular intervals as required by the standard. This is causing the default ipv6 route to expire after the initial 5400s timer. So it appears to be a Telus local edge router problem. Now the challenge will be to get past technical support to report this.

Paul_C
Friendly Neighbour

I'm experiencing this exact issue.

 

Any luck with this?  Extremely annoying...

valiaig
Advisor

@RR923 wrote:

I need to update my original analysis. The default route in ipv6 is provided by ICMP RA (Router Advertisement) messages not DHCPv6. From my packet capture, it appears that the Telus edge router is only sending RAs as a response to a Router Solicit, not at regular intervals as required by the standard. This is causing the default ipv6 route to expire after the initial 5400s timer. So it appears to be a Telus local edge router problem. Now the challenge will be to get past technical support to report this.


Have you tried to check if there is Firmware available?  I remember having dsmr issue until representative re-flashed their T3200m 

Paul_C
Friendly Neighbour

One other thing I noticed is that even if I put in a switch between the ONT and the TELUS modem, then hook up my own router to the switch adjacent to the TELUS modem, the problem still occurs.  This leads me to believe that the issue is either with the ONT, or in how TELUS is handling IPv6.

 

Thoughts?

YVRcub
Friendly Neighbour

@RR923 wrote:

I need to update my original analysis. The default route in ipv6 is provided by ICMP RA (Router Advertisement) messages not DHCPv6. From my packet capture, it appears that the Telus edge router is only sending RAs as a response to a Router Solicit, not at regular intervals as required by the standard. This is causing the default ipv6 route to expire after the initial 5400s timer. So it appears to be a Telus local edge router problem. Now the challenge will be to get past technical support to report this.


Any updates? fix?

Because all this would explain why I'm so much issues with mine too... and have to reboot my modem way too many times Smiley Sad