Re: Why wireless interface cannot be attached to a Linux host bridge?

ryotaro kobayashi
Wed, 08 Jul 2020 00:20:14 -0000

Thank you for your reply.

Please let me sure.

> 1) the way that almost all wireless connections work (only traffic
to/from a single MAC address is allowed on a particular wireless
 connection).

> 2) Because of (1), the Linux kernel doesn't allow wireless network
devices to be attached to a Linux host bridge device.

So, what you are saying is the authentication between wireless access point
and client ? ( For example ,I think if linux pc allowed each wireless
bridge ,more authentication is needed to another access point. )

Or ,Because of is it hard to treat four MAC addresses these are needed to
bridge (src/dest MAC adresses in each wired nework and wireless network)?

Sorry for I'm getting off track of libvirt.

Best regards.

P.S. Thanks for the compliment on the machine translation. I'm getting
happy too :-)

2020年7月8日(水) 1:43 Laine Stump <laine@redhat.com>:

> On 7/7/20 11:26 AM, ryotaro kobayashi wrote:
> > Hello, everyone.
> >
> > I'm from japan and using machine translation, so I apologize if
it's
> > hard to read.
> >
> > I am currently trying to build a virtual environment using Ubuntu and
> kvm.
> >
> > However, I found out from the following page that the virtual machine
> > cannot use the bridge network because I am using a wireless network.
> >
> > https://wiki.libvirt.org/page/Networking
> >
> > I am having trouble with this because my PC is using a wireless LAN.
> >
> > On that page it says "wireless interfaces cannot be attached to a
Linux
> > host bridge",  I Can you tell me why this is so?
> >
> > Is it a limitation of the NIC driver for the wireless LAN?
>
> Not really.
>
> > Or is it a limitation of libvirt?
>
> Definitely not. Completely out of libvirt's control.
>
>
> It is a limitation of
>
> 1) the way that almost all wireless connections work (only traffic
> to/from a single MAC address is allowed on a particular wireless
> connection).
>
> (Yes, I know there are some wireless modes that allow multiple MAC
> addresses on a single association. But those modes aren't supported by
> most wireless APs or clients.)
>
> 2) Because of (1), the Linux kernel doesn't allow wireless network
> devices to be attached to a Linux host bridge device.
>
>
> Some people have had success with IPv6 by enabling proxy ARP on the
> bridge device and wireless interface (without directly attaching them to
> each other, then manually adding a host route pointing to the guest's
> IP. It might be possible to do something similar for IPv4 using proxy
> ARP, but I personally haven't played with the idea.
>
>