On Sun, Mar 16, 2008 at 05:50:19PM +0100, Daniel Stodden wrote:
> On Sun, 2008-03-16 at 15:52 +0100, Pavel Muller wrote:
> > Hello,
> > I want to ask if XEN use TUP/TAP interfaces or use other interface?
>
> No. TUN/TAP is typically used for hosted VMs. Broadly speaking, it's
> only useful if a significant part of the VMM is running in user mode on
> top of a native Linux, as is the case with VMware Workstation,
> VirtualBox, UserModeLinux etc.
>
> Xen is a hypervisor, running below all OSes on bare hardware. The
> network virtualization is based on a Linux OS (dom0), but the guests
> aren't running on top of that, but rather as siblings on a common
> virtualization layer.
Whether it is a separate hypervisor / Dom0, or a combined HV+Dom0 is not
really relevant to this question. In both cases the driver backends are
in the Linux host OS and not the hypervisor itself.
>
> There's a dedicated interface class (vifN.M) in dom0. The purpose is
> similar, but the interplay with guests is quite a different one.
This is correct for paravirt guest or PV drivers, but is wrong for fullvirt.
The QEMU device model used for fullvirt guests *does* use TUN/TAP devices
as the backend for its emulated ne2k/rtl8139 NICs.
Dan.
--
|: Red Hat, Engineering, Boston -o- http://people.redhat.com/berrange/ :|
|: http://libvirt.org -o- http://virt-manager.org -o- http://ovirt.org :|
|: http://autobuild.org -o- http://search.cpan.org/~danberr/ :|
|: GnuPG: 7D3B9505 -o- F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :|
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
|