Re: Cannot start a Linux domU: "Device 768 (vbd) could not be connected"

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Tue, Jun 09, 2009 at 09:51:21PM +0200, Stephane Bortzmeyer wrote:
> I have a NetBSD dom0 "NetBSD 5.0 (XEN3_DOM0)". It boots and xend
> starts.
> 
> But I cannot start a Linux domU. The default Debian/Linux kernel is
> not accepted:
> 
> 'Invalid kernel', 'xc_dom_compat_check: guest type xen-3.0-x86_32p not
> supported by xen kernel
> 
> Googling finds pages explaining that 'p' in "xen-3.0-x86_32p" is for
> PAE and that a NetBSD dom0 does not support PAE :-(

that's not exactly true. A amd64 NetBSD dom0 kernel will accept i386PAE
guests (NetBSD or Linux). You can also have a i386PAE NetBSD dom0 kernel
if you run -current.

> 
> All the binary Linux kernels I can find are compiled for
> PAE. <http://www.netbsd.org/ports/xen/howto.html#linux-domU> says
> "using one of the vmlinuz-*-xenU kernels available in the Xen binary
> distribution" But I do not find such distribution, I only have
> <http://www.xen.org/download/> which distributes patched Linux
> sources. So I compile a Linux kernel without PAE (not easy because the
> Kconfig forces the use of PAE) but it does not boot:
> 
> % sudo xm create -c /usr/pkg/etc/xen/oroshi.cfg
> Using config file "/usr/pkg/etc/xen/oroshi.cfg".
> Error: Device 768 (vbd) could not be connected. Hotplug scripts not working.

I guess /dev/wd0k and /dev/wd0l exists ?
Do you have any relevant message in /var/log/xenbackendd.log ?
What do you have in the dom0's dmesg (if the kernel itself has problems
connecting to these devices, it'll print error message here).

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
--