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Date: Thu, 15 Oct 2009 09:44:42 +0200
From: Gleb Natapov <gleb@redhat.com>
Subject: Re: [Qemu-devel] Re: [PATCH-updated] qemu/net: add raw backend
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To: Or Gerlitz <ogerlitz@voltaire.com>
Cc: Arnd Bergmann <arndbergmann@googlemail.com>, qemu-devel@nongnu.org, "Michael S. Tsirkin" <mst@redhat.com>

On Thu, Oct 15, 2009 at 09:29:34AM +0200, Or Gerlitz wrote:
> Gleb Natapov wrote:
> > tap need IP assigning.
> 
> Hi Gleb, please correct me if I'm wrong, but the way we use tap here is attach it to a bridge from the one hand, and have Qemu write/read into/from it Ethernet frames from the other hand. This means that even the MAC address of tap isn't used, surely not an IP address.
> 
Yes, you are right. I don't use tap usually so I don't remember. What
I really mean is that guest needs IP assigning, so this means I need
external DHCP setup.  Slirp has (almost) everything you ever need from
networking and with zero config: dhcp address assigning, NATing your
traffic and as a bonus no need to run as root. Hard to beat that if you
don't need performance.  Raw requires root and external dhcp so it lose
two point to slirp and it doesn't win any for my use case. But we have
a lot of crap^W features in qemu anyway so don't see why not add this too.

--
			Gleb.