Linux

cross-posted from: https://feddit.de/post/6970687

I operate a Debian router. IPv4 works perfectly. However, I am facing issues with IPv6.

In my sysctl.conf, I have the following configuration:

# accept router advertisements on WAN interface
net.ipv6.conf.1und1.accept_ra = 2

In /etc/systemd/network/1und1.network, the configuration is as follows:

[Match]
Name=1und1

[Network]
Description=Fritz!Box 7510 providing 1und1 VDSL
IPv6AcceptRA=yes
DHCP=yes

[DHCPv4]
Hostname=claptrap
UseHostname=no
UseDNS=no
UseNTP=no
UseSIP=no
UseRoutes=no
UseGateway=yes

[IPv6AcceptRA]
UseDNS=no
# Force starting the DHCPv6 client even if the Router Advertisement
# indicates it's not required.
DHCPv6Client=yes

[DHCPv6]
UseHostname=no
UseDNS=no
UseNTP=no

In my dnsmasq.conf, the configuration is as follows:

dhcp-range=interface:br0,::,constructor:br0,ra-stateless,ra-names,12h

Additionally, the /etc/nftables.conf contains:

icmpv6 type {
    echo-request,
    nd-neighbor-solicit,
    nd-router-solicit,
    mld-listener-query,
    nd-neighbor-advert,
    nd-router-advert
} accept

On the WAN interface.

I receive a /64 IP on the 1und1 interface; however, I do not receive a prefix on br0. What am I doing wrong? Do I need to instruct systemd-networkd to request a larger prefix somehow?