Re: Switching from IDE to virtio_blk [qas Re: [Fedora-xen] Goodbye Xen on RH/Fedora?]
On Wed, Jan 21, 2009 at 03:06:43PM +0100, Emre Erenoglu wrote:
On Wed, Jan 21, 2009 at 2:48 PM, Mark McLoughlin
<markmc(a)redhat.com> wrote:
> (This is all getting offtopic for fedora-xen, we should really move to
> fedora-virt)
>
> On Wed, 2009-01-21 at 14:28 +0100, Jan ONDREJ (SAL) wrote:
> > virtio_net works well, but I have trouble to boot from virtio_blk.
> >
> > I can add second disk as virto block device, but I can't boot from
> > first disk.
>
> When switching from IDE to virtio, you need to first build a new initrd
> in the guest with e.g.:
>
> $> mkinitrd --with virtio_pci --with virtio_blk -f
> /boot/initrd-$(kernelversion) $(kernelversion)
>
> You only need to do this once. After that, if a new kernel is installed
> while you're booted off a virtio disk, then mkinitrd will include the
> modules automatically.
You will also need to specify /dev/vdX on the kernel root= line and make
sure your init script inside your initrd triggers the virtio drivers at boot
so that the /dev/vdX are created.
Yes I have to agree with Emre here - I don't think it's as simple as
just rebuilding mkinitrd. I got that far but gave up later on.
/me checks notes ...
Yup, I got as far as working out that you would have to edit fstab and
possibly /boot/grub/device.map and /boot/grub/menu.lst, before giving
up.
If anyone would like to fill in the wiki page here on the subject:
http://wiki.libvirt.org/page/Virtio
I'd like to reiterate that _none_ of this complexity is required when
installing a new guest. Anaconda sets up everything for you.
Rich.
--
Richard Jones, Emerging Technologies, Red Hat http://et.redhat.com/~rjones
virt-df lists disk usage of guests without needing to install any
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http://et.redhat.com/~rjones/virt-df/