BT FTTP - ONT VLAN Tagging - Google/Nest WiFi IPv6

[Sicario]

I’m running Google WiFi (Nest Router), with the WAN port hooked up directly to the ONT. Its the one port style with a BBU.

I have my WAN set up to login over PPPoE and pull IPv4 without issue, but I can’t get IPv6 to work. The toggle is simply greyed out, and for others it says the ISP doesn’t support IPv6.

The web chat suggests it’s because the ONT is using VLAN tagging - does anyone know if this is the case? 

Has anyone managed to get IPv6 working with Google WiFi and BT? 

I’ve escalated the issue to check whether the nest is able to send a 56 PD delegation, will update if I hear back.

Thanks! 

[Sicario]

As an update, I managed to get the option for IPv6 enabled, though it’s still not working.

It says it’s not supported by the ISP - I have a managed switch arriving tomorrow to test the VLAN tagging theory.

The toggle being broken is an issue with the iOS app. I loaded an Android emulator to use the Google Play Store version of Google WiFi, and lo and behold it worked straight away.

Will update.

[Dialupp]

How did you get on?  I'm having similar issues...

[Dialupp]

I've found that if you click on the IPv6 page and then LEARN MOREand then go back by pressing the X, you can enable IPv6.  However it can't connect.  It says IPv6 is on, but cannot be used right now.  We'll keep trying.

I'm going to see if I can get BT to turn Vlan tagging off.

[Sicario]

No difference with a managed switch in between the ONT and Nest router. 

I don’t think the traffic is tagged. There would surely be lots of issues with my ipv4 connection if that was the case. 

Theres another thread where two people have got ipv6 enabled on their connection temporarily, but they lose it after a while. 

Would be interested in how you get on with BT!

[Dialupp]

So BT won't/can't turn it off.  Openreach possibly, but I doubt it.

[Sicario]

They confirmed the ONT has vlan tagging on the line?

[Sicario]

I think the ONT tags traffic on the outgoing side to connect to the open reach network, but traffic inside shouldn’t be tagged. 

Can anyone point me to a specifications sheet for third party router IPv6 compatability? 

[BonzoG]

For what it's worth, although it doesn't directly help you with Nest, I've had IPV6 working "out of the box" with both an Asus router and a Linksys OpenWRT device using native DHCP-PD over the PPP interface.

No VLAN tagging required between the router and the ONT - in fact this broke the connection, when I originally tried to use my old FTTC PPPoE settings.

I'm fairly sure on this basis that FTTP connections don't require a VLAN ID to be set on the customer side, if it's done anywhere it's by the ONT on the WAN side. I'll find out for sure shortly as I am also planning to install a managed switch between the ONT and my router, whilst rewiring the house.

[newbee101]

Hi, I am in a similar situation.

Using Nest Wifi directly with the BT ONT (FTTH) router is causing drop in speed.

Some research online revealed that this is a VLAN tagging issue and Nest Wifi doesn't support this.

Using the BT router and configuring Nest Wifi as DHCP works but I am expectedly running into

double NAT trouble with this

I purchased  aTP link managed switch to put between the ONT & Nest Wifi as advised on the Nest Wifi site. However I am struggling with setting up the VLAN settings to make this work.

Any help or signposting would be most appreciated.