On 2023-11-16 16:49, Gregory Nowak via Dng wrote:
> I see from output you posted previously your router supports stateful
> address configuration, but you didn't post any output regarding
> autonomous address configuration. I don't expect the following to make
> a difference, but just in case, can you change in
> /etc/network/interfaces:
>
> iface eth0 inet6 dhcp
>
> to:
>
> iface eth0 inet6 auto

With this setting, eth0 does not get a routeable IPv6 address.

eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
         inet 192.168.1.12  netmask 255.255.255.0  broadcast 192.168.1.255
         inet6 fe80::16da:e9ff:fef9:aa5c  prefixlen 64  scopeid 0x20<link>
         ether 14:da:e9:f9:aa:5c  txqueuelen 1000  (Ethernet)
         RX packets 943  bytes 119440 (116.6 KiB)

My router is set to its defaults for IPv6:

Dynamic IP (with options Dynamic, PPPoE, 6to4, Bridge)
Get IPv6: Auto (with options Stateful, Stateless, Non-Address, Auto)
Prefix Delegation: On
DNS Address: Auto
Assigned Type: DHCPv6 (with options ND Proxy, SLAAC+Stateless DHCP,
DHCPv6, SLAAC+RDNSS)

-Michael