I'm having trouble getting IPv6 to work for my KVM/qemu guests.
I have two bridges setup, one routed (external, non libvirt) bridge for
public dedicated ipv4 + ipv6 which works for both protocols.
Then I have a libvirt nat bridge (with the routed bridge as parent) with
a nated ipv4 (that works) and I also want a public ipv6. I'm able to
transmit udp packets out but I never get any response.
Looking at tcpdump there are incoming neighbor solicitations that get
unanswered and don't get forwarded to the guest.
Do I need to set something special up for this to work? Ubuntu 22.04 /
Libvirt 8.0.0
The routed bridge (pubBr) has ipv6 2001:x:x:7d8e:: - My nat bridge
config below:
<network>
<name>natbr</name>
<bridge name="natbr" />
<forward mode='nat' dev='pubBr'>
<nat>
<port start='8000' end='30000'/>
</nat>
</forward>
<ip address="10.1.1.1" netmask="255.255.0.0">
<dhcp>
<range start='10.1.1.2' end='10.1.1.255'/>
</dhcp>
</ip>
<ip family="ipv6" address="2001:x:x:7d8e::1"
prefix="64">
<dhcp>
<host name="test" ip="2001:x:x:7d8e:a01:2ff::"/>
</dhcp>
</ip>
</network>
Thanks!