Speed Test doesn't work with IPv6 mobile network

As per the title: Speed Test has stopped working once I changed my mobile interface to IPv6. I don’t think this is the same problem as in this post:

Because all I get is “Failed to retrieve provider IP address. Please check your internet connection.”

I can’t even see upload speeds - it won’t even choose a Server.

@Marijus do you know if this will be fixed in the upcoming firmware release too?

Many thanks.


As the error message states, do you have stable internet connection on IPv6 interface?

Kind regards,

@Marijus I do apologise.

Because I still had access (through Tailscale) to the RUT360, I ASSUMED that everything was working, but it wasn’t.

Just now I have gone down a rabbit hole of trying to understand why IPv6 doesn’t work on EE/BT and the conclusion I have come to is that it just isn’t possible - I haven’t come across anyone doing it successfully.

Which is a shame, as I was hoping it would mean Tailscale could operate without a relay.

Apologies again.


No issue at all! If you have any other questions, feel free to ask us anytime.

Best regards,

Thank you Marijus

I do have a couple of quick questions that are related to this topic, if that’s OK?

The mobile network my 4G Teltonika devices usually connect to in the UK is EE, and as far as I know EE uses 464XLAT.

  1. Does that mean that I must use a 4G router with 464XLAT support for IPV6 to work?

  2. If so, is Teltonika planning to add support for 464XLAT in a future firmware update?

(The device I wanted to work better with Tailscale is a RUT360.)

All the best,


Teltonika already supports IPv6. You can configure it for both mobile and WAN connections.

However, ensure that your internet service provider also supports IPv6. Sometimes, you may need a different APN to enable this functionality, as IPv6 isn’t widely used in Europe.

Best regards,

Thank you Marijus - I did try IPv6, and the RUT360 connected fine and was given an IPv6 address by EE, which worked for IPv6 but then everything on the LAN using IPv4 seemed to fail. (And the router lost connection completely when I selected the ‘IPv4/IPv6’ option.)

I assumed it was connected to this post:

and that this is why it is failing? :grimacing: