Xen Hurd: Error: Device 768 (vbd) could not be connected

[Shakthi Kannan]

Hi,

I am trying to run Hurd with Xen as per the documentation:
http://youpibouh.thefreecat.org/hurd-xen/DOC.txt

on a HP Compaq nx7400 laptop running Debian GNU/Linux (Lenny/sid). I
have installed all the .deb from the above URL as well as
xen-hypervisor-3.2-1-i386-nonpae. Copied gnumach-xen, hurd-modules to
/boot. My /etc/xen/hurd is as follows:

=== Hurd ===

kernel = "/boot/gnumach-xen"
memory = 256
disk = ['phy:hda1,hda,w']
extra = "root=device:hd0"
# vif = [ 'dhcp' ]
ramdisk = "/boot/hurd-modules"

=== END ===

I booted into the Xen 3.2-1-i386-nonpae / Debian GNU/Linux, kernel
2.6.18-6-xen-686-nonpae. When running 'sudo xm create -c hurd', I get
the following output:

=== OUTPUT ===

Using config file "/etc/xen/hurd".
Error: Device 768 (vbd) could not be connected. Hotplug scripts not working.

=== END ===

Is the value of disk in /etc/xen/hurd file correct? I have / in
/dev/sda1, /home in /dev/sda2, swap in /dev/sda3. Appreciate any help
in this regard,

Thanks!

SK

[Samuel Thibault]

Post by Shakthi Kannan
Using config file "/etc/xen/hurd".
Error: Device 768 (vbd) could not be connected. Hotplug scripts not working.

Check xend logs.
Just to make sure: hda1 is not mounted in dom0, right?

Samuel

[Shakthi Kannan]

Hi,

--- On Mon, Sep 1, 2008 at 1:34 AM, Samuel Thibault
<***@ens-lyon.org> wrote:
| hda1 is not mounted in dom0, right?
\--

There is no hda1 on the system, only sda1 (/), sda2 (/home), sda3
(swap). Do we need to specify a mounted partition or what does this
disk signify in /etc/xen/hurd?

SK

[Samuel Thibault]

Post by Shakthi Kannan
--- On Mon, Sep 1, 2008 at 1:34 AM, Samuel Thibault
| hda1 is not mounted in dom0, right?
\--
There is no hda1 on the system, only sda1 (/), sda2 (/home), sda3
(swap).

Then specify sda1...

Post by Shakthi Kannan
Do we need to specify a mounted partition or what does this disk
signify in /etc/xen/hurd?

If you could read the xen doc that could help :)

disk = ['phy:hda1,hda,w']

means /dev/hda1 in the host system, hda in the guest system.

Samuel

[Shakthi Kannan]

Hi,

--- On Mon, Sep 1, 2008 at 9:04 PM, Samuel Thibault
<***@ens-lyon.org> wrote:
| If you could read the xen doc that could help :)
\--

Yes, will do.

---
| disk = ['phy:hda1,hda,w']
|
| means /dev/hda1 in the host system, hda in the guest system.
\--

I have / in /dev/sda1 in my host system. So, I tried:

disk = ['phy:sda1,sda,w']

IIRC, in Hurd with GNU Mach, there is no SCSI support? Anyways, I
proceeded to do:

sudo xm create -c hurd

=== OUTPUT ===

Using config file "/etc/xen/hurd".
xenconsole: Could not read tty from store: No such file or directory

=== END ===

I got the prompt back. I tried "sudo xm list" and the output was:

=== OUTPUT ===

Name ID Mem VCPUs State Time(s)
Domain-0 0 731 2 r----- 467.7
hurd 2 256 1 --p--- 0.0

=== END ===

But, should we see some console log output or boot messages? After few
seconds, I get " Error: Device 2048 (vbd) could not be connected.
Hotplug scripts not working." message. I now try to do "sudo xm list",
and I get only Domain-0 in the output:

=== OUTPUT ===

Name ID Mem VCPUs State Time(s)
Domain-0 0 731 2 r----- 474.1

=== END ===

=== /var/log/xen/xend.log ===

[2008-09-01 07:11:54 21821] DEBUG (XendDomainInfo:1897)
XendDomainInfo.destroy: domid=2
[2008-09-01 07:11:54 21821] DEBUG (XendDomainInfo:1914)
XendDomainInfo.destroyDomain(2)
[2008-09-01 07:11:54 21821] DEBUG (XendDomainInfo:1529) Destroying device model
[2008-09-01 07:11:54 21821] DEBUG (XendDomainInfo:1536) Releasing devices
[2008-09-01 07:11:54 21821] DEBUG (XendDomainInfo:1542) Removing vbd/2048
[2008-09-01 07:11:54 21821] DEBUG (XendDomainInfo:590)
XendDomainInfo.destroyDevice: deviceClass = vbd, device = vbd/2048
[2008-09-01 07:11:54 21821] DEBUG (XendDomainInfo:1542) Removing console/0
[2008-09-01 07:11:54 21821] DEBUG (XendDomainInfo:590)
XendDomainInfo.destroyDevice: deviceClass = console, device =
console/0
[2008-09-01 07:11:54 21821] DEBUG (XendDomainInfo:1534) No device model
[2008-09-01 07:11:54 21821] DEBUG (XendDomainInfo:1536) Releasing devices

=== END ===

1. Do we need to specify anything to get the console output? On
running "sudo xm create -c hurd", are we expecting some output?
2. If there is no SCSI support in GNU Mach, but, host system uses
sdaX, what parameters do we need to use for 'disk'?

Thanks,

SK

[Samuel Thibault]

Hello,
Err, I don't understand. Are you meaning that /dev/sda1 contains the /
of dom0? If yes then no you shouldn't use

Post by Shakthi Kannan
disk = ['phy:sda1,sda,w']

The first argument is where the _guest_ / is as seen from dom0.

Post by Shakthi Kannan
IIRC, in Hurd with GNU Mach, there is no SCSI support?

That's where para-virtualisation is useful. The "sda" above is just a
name, the name under which the disk will appear in the guest. It happens
that in Mach, be the disk IDE or SCSI it will appear as /dev/hd0, so
I've made the Xen support so that you can set sda or hda, that will just
be the same.

Post by Shakthi Kannan
1. Do we need to specify anything to get the console output?

You have already done so: that's the -c option.

Post by Shakthi Kannan
On running "sudo xm create -c hurd", are we expecting some output?

When it runs fine, yes, you should get the kernel messages.

Post by Shakthi Kannan
2. If there is no SCSI support in GNU Mach, but, host system uses
sdaX, what parameters do we need to use for 'disk'?

See above.

Samuel

[Shakthi Kannan]

Hi,

--- On Tue, Sep 2, 2008 at 10:40 PM, Samuel Thibault
<***@ens-lyon.org> wrote:
| Err, I don't understand. Are you meaning that /dev/sda1 contains the /
| of dom0?
\--

Yes.

---
| If yes then no you shouldn't use
\--

Ok. Thanks!

SK