Subject: Re: Booting a NetBSD 4 domU on a Linux dom0?
To: Chris Ross <email@example.com>
From: Manuel Bouyer <firstname.lastname@example.org>
Date: 03/29/2007 10:19:40
On Wed, Mar 28, 2007 at 05:35:36PM -0400, Chris Ross wrote:
> I did some googling around, and found mostly information in the
> archives of this mailing list. I hope this isn't a question that's
> been answered "too many times".
> The information I found seemed to mostly deal with running a
> NetBSD dom0, of course, and with older versions of NetBSD.
The changes to use a linux dom0 should only be marginal, and you'll spot
them easily (device names in the config file, mostly) if you already have
a linux domU running.
> I have
> NetBSD 4ish (the current top of the netbsd-4 branch) built, and want
> to run it on a big machine I have at work running Xen 3.0.3 with an
> Ubuntu 6.06 userland. This is an amd64 machine, running on a machine
> with HVM support, so it can do full virtualization, but I don't want
> it to.
Running 32 or 64bit linux ? NetBSD/Xen only runs on 32bit hosts for now.
> What would I have to do to create a domU that I could install
> NetBSD onto? Does the ISO generated with the new 'iso-image'
> build.sh target know how to boot a para-virtualization aware kernel
> on a machine?
For Xen native domU, the kernel is loaded from dom0's filesystem.
the disk/cdrom/whatever images used for virtual disks are only used once
the kernel is running.
What you need to do the install is the netbsd-INSTALL_XEN3_DOMU.gz kernel.
Once the install is complete, halt the domU and boot it with
> I don't want to end up running fully virtualized,
> which I suspect is what would happen with a GENERIC kernel. Is it
> even possible/practical to run para-virtualized with i386 on an amd64
This I don't know, I've never tried it on a 64bit OS. I ran NetBSD/i386
on a para-virtualized guest on a i386 dom0, and it's as fast as a native Xen
guest for CPU-bound tasks. I/O are slow.
> If I build amd64 netbsd-4 code, can that run under a linux
> dom0 (126.96.36.199-xen) ?
No, we don't have 64bit support in Xen yet.
Manuel Bouyer <email@example.com>
NetBSD: 26 ans d'experience feront toujours la difference