I’ll answer here myself…

The problem has apparently been solved.

The probable cause was that the clients were probably still using addresses that had previously been assigned via the router advertising (radvd). The old addresses were no longer part of the advertisements (checked with radvdump).

After a client restart they were gone and the clients now used the most current addresses and then it worked.

I’ll leave it like that - maybe it will help someone.

@SkyBeam

If you don’t have a static prefix (which Swisscom doesn’t offer on private connections), you might be able to pay attention in the future to how often the prefix is ​​renewed by Swisscom on the network side, in order to deal with the delegated dynamic prefix in one local network, I think this is crucial information, which Swisscom has not yet communicated.

@MichelB

Maybe some information about the renewal interval of the dynamic IPv6 prefix for private customers in the Swisscom network?

@Werner

Sure, I can do it. Or I should see this in my DDNS statistics because it is logged here when the IP changes - and thus also the prefixes.

Theoretically, there are no reasons to change the IPv6 prefix. At least not as long as the CPE doesn’t go offline and the lease expires (recycling). There should be enough addresses/prefixes available so that they can remain virtually static.

EDIT: I just saw that my DDNS provider only offers statistics for 1 month. So I’ll probably have to look in there more often or do something else. Hopefully nothing changes that often.

Does anyone know the correct IPv6 native settings for the Fritz boxes? But I get the diagnostic information: “Internet connection IPv6 could not be established: No response from DHCPv6 server (SOL)”.

😕

2022-12-17 Edit: Dualstack to IPv6 Native.

🤷‍♂️

@andiroid

I don’t have a Fritzbox myself and therefore don’t know the specific detailed options that are offered to you when you switch on the IPv6 connection.

From a network perspective, the obvious operating modes would be “Native” or “Dual Stack” and if you have to specify a prefix length, I would try 56.

@Werner

Or prefix length 58, at least that’s what my dhcpcd says you can get from IB2.

wan: delegated prefix 2a02:1210:xxxx:xxxx::/58

It might be better to deal with the individual topics in their own threads. Regarding FRITZ!Box you could continue this here: [https://community.swisscom.ch/t5/Router-Hardware/IPv6-nativ-mit-FritzBox/td-p/711115](https://community.swisscom. ch/t5/Router-Hardware/IPv6-nativ-mit-FritzBox/td-p/711115) There it is Actually, there are tips that could possibly work now.

Otherwise, unfortunately, like in the “SRG channel finally in Full HD” there will be a hijack and then unfortunately people will discuss home installations with switches, etc., bypassing the actual thread. I actually find it tedious.

Then it would of course be important to mention how you want to operate the FRITZ!Box. Directly on the WAN or via PD on the Internet Büx.

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@Tux0ne wrote:

It might be better to deal with the individual topics in their own threads. Regarding FRITZ!Box you could continue this here: [https://community.swisscom.ch/t5/Router-Hardware/IPv6-nativ-mit-FritzBox/td-p/711115](https://community.swisscom. ch/t5/Router-Hardware/IPv6-nativ-mit-FritzBox/td-p/711115) There it is Actually, there are tips that could possibly work now.

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Thanks for the tip, we’ll do it!

😉👍

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@Werner wrote:

@SkyBeam

If you don’t have a static prefix (which Swisscom doesn’t offer on private connections), you might be able to pay attention in the future to how often the prefix is ​​renewed by Swisscom on the network side, because for dealing with the delegated dynamic prefix in In a local network, I think this is crucial information, which Swisscom has not yet communicated.

@MichelB

Maybe some information about the renewal interval of the dynamic IPv6 prefix for private customers in the Swisscom network?

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@Werner I have experience from my Anschluss:

- the IPv4 has not changed since mid-May 2021 -> so the same public IPv4 address for 1 ½ years

- the IPv6 has not changed since the end of February 2022 -> so the same public IPv6 address for over 9 months.

My Internet Box Plus still seems to be trying to use a 6th ipv6 and I can no longer get a working ipv6 connection

Firmware version actually looks good, I updated it manually

Firmware version 11.04.22/11.04.20

I also tried rebooting several times but without success

Disable and re-enable IPv6?

Only a complete reset helped me.

• Save configuration
• Box reset
• Restore configuration

If you use the standard configuration (most home users without NAS, port forwarding, etc.) you can save the backup and just do a reset.

Thanks! That was exactly the problem.

After the reset (I had already tried deactivating and activating without success) I was able to activate it and now it also works with my openwrt router (without any changes).

As already suspected, you need the internet box to activate this and then it also works with third-party routers.

@Peiffegreu33 is a bit OT: It’s the same problem if you want to use a landline.

You have to activate the Swisscom router once on Anschluss, otherwise it won’t work with the 3-party router!!!

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@SkyBeam wrote:

Only a complete reset helped me.

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Uh, that’s relatively unfortunate if that’s the case everywhere. Especially since the migration is described as complete.

A large proportion of customers are not interested in the technology at all and are essentially left in limbo.

@Tux0ne

The majority of customers probably don’t care at all whether they have v6 via 6rd, natively or no v6 at all.

Exactly. That’s why it doesn’t matter if the router distributes addresses via the 6th prefix but it doesn’t work. You have a dual stack. Still, problem not understood…

From the end customer’s perspective, a problem is only a problem when they perceive it as such, for example because something no longer works. And this is precisely the case that does not occur thanks to the dual stack.