Seem to only have IPv6 connections now!

Yesterday afternoon my son started having internet issues. Some sites work and others don't.

Using a "what is my ip address" web site, it's only seeing an IPv6 connection and not an IPv4 one.

Commands like ping -6 www.google.com work while ping www.google.com don't.

Has anyone else experienced this recently with Zen?

Is it possible that your son's connection was affected by the recent round of IPv4 reallocations, and his old IPv4 address(es) are hard-wired into his router or other configuration?

He can check his IPv4 allocation on the My Services part of the Zen portal.

I had my IPv4 allocation changed recently, but both IPv4 and IPv6 are working here (Zen FTTP; Openreach with BT Wholesale backhaul).

We rebooted the router after the IP address change and all was working well until yesterday afternoon.

IPV6 is fine but IPv4 does not. TRACERT show's packets leaving the router and getting to Zen but then no further. I can ping his router via IPv4 but he can't ping my last public hop - I'm on Starlink.

His first hop outbound to me and my last one inbound to him are different and I suspect a configuration issue in Zen's network.

In reply to a post by bsdnazz:

IPV6 is fine but IPv4 does not. TRACERT show's packets leaving the router and getting to Zen but then no further. I can ping his router via IPv4 but he can't ping my last public hop - I'm on Starlink.

Routers, especially at the edge of service provider networks, often block pings. It's hard to draw conclusions from that.

In reply to a post by bsdnazz:

His first hop outbound to me and my last one inbound to him are different

That is almost always the case. A router has multiple interfaces: when you are tracerouting through it, you will see the IP address of the interface nearest you. (That is, the one it originates the ICMP "TTL exceeded" message from)

I suggest you raise a case with Zen with symptoms not causes: give examples of specific websites you cannot reach. Don't try to diagnose it yourself.

However, if you can ping 2001:4860:4860::8888 but cannot ping 8.8.8.8, that is a good diagnostic / smoking gun.

In reply to a post by bsdnazz:

I can ping his router via IPv4

How do you know the IPv4 address of his router? Is this from the Zen account info page, or by logging into the router and showing the IPv4 address on the WAN interface, or something else?

If you're looking at the router config, does it have a statically-configured WAN address, or is it picking it up dynamically via PPP?