Re: Problems booting NetBSD/Xen on Intel NUC 12 Extreme w/ i9-12900

[mlelstv%serpens.de@localhost (Michael van Elst)]

c%bow.st@localhost ("Mathew\, Cherry G.*") writes:

>>>>>> "Brad" =3D=3D Brad Spencer <brad%anduin.eldar.org@localhost> writes:
>    >> The only remaining show stopper issue at the moment seems to be
>    >> that I have yet to be able to bridge Internet connectivity into a
>    >> DOMU from my 10_BETA DOM0 (yes, the ure0 that I use for access
>    >> and the xvifNiM are connected to the same bridge, which is up,
>    >> and, yes according to sysctl both v4 and v6 forwarding is
>    >> active).

Bridging the xvif interfaces should just work.

forwarding is about routing packets, it's not necessary for a bridge.


>    Brad> I am not suggesting that this is the problem you are having,
>    Brad> as I am not 100% sure what sort of thing your ure0 is, but I
>    Brad> have had trouble in the past when the external interface of
>    Brad> the DOM0 is a 802.11 NIC.

Bridging on a wifi interface doesn't work. For bridging, the interface has
to send packets with MAC addresses that are not its own, but a regular client
is identified by its MAC address.

There is a special wifi 4 address mode, but it's not supported in all
networks (nor by our wifi stack). You also need hardware that can actually
send packets with foreign MAC addresses (i.e. anything that supports hostap
mode).


>I think this is not Xen specific - when you bridge multiple VMs to the
>same physical NIC, you need a sort of L2 NAT (I believe on Linux this is
>called macvlan)

You can bridge VMs on a virtual bridge just like you can bridge physical machines
on a physical bridge.

macvlan on Linux is an optimized bridge. You can create virtual sub-interfaces
that are bridged with the host interface and use the sub-interfaces for virtual
machines or usually: containers. Since you configure the (random) MAC addresses
on the host it doesn't have to learn them. This makes starting containers faster.