Hi Paul.

12 Oct 21 15:43:00, you wrote to me:

 TK>> I think your problem is somehere in your router PI, you should open ports
 TK>> 24554-24555 there as well. But as I'm no linux expert, I dont think I
 TK>> can help much more.

 PH> So look at the Raspberry Pi that acts as the end point of the tunnel?

At that PI you should open and/or forward ports. Which OS are you running there?

 PH> The main router connected to the internet does have 24554-24555 open
 PH> already, and IPv4 traffic coming in via my ISP works OK

At the main router it is needed only to open protocol 41 from he.net to your PI so that the tunnel works. Anything else on the IPV4 side is irrelevant.

In my Ubuntu:

tommi@pin:~$ sudo ufw status|grep ipv6
Anywhere                   ALLOW       216.66.84.46/ipv6

But all this seems to be working at your setup...

'Tommi

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