[one-users] Using Xen phy devices in VM templates

[Stefan Freitag]

Dear all,

at present I am using OpenNebula 1.4 to deploy virtual appliances
to a Xen-based compute cluster. On each of the cluster nodes there
exists a hard disk partition that should be used as scratch directory
inside the virtual appliance (only 1 appliances is assigned to 1 server
at a time, so there is no conflict).


I created a template to describe the appliances and got stuck. Here is
what I did so far concerning the hard disks used in the virtual
appliance:

1) that is the image containing the OS, boot and root directory
DISK = [
    source   = "/mnt/gridconfig/images/workernode/wn_sl54_x86_64.img",
    target   = "xvda",
    readonly = "no" ]

2) a swap partition that is created on the fly by OpenNebula
DISK = [
    type = swap,
    size = 1024,
    target   = "xvdb",
    readonly = "no" ]


3) I thought that this could work
DISK = [
    source="/dev/cciss/c0d0p4",
    target   = "xvdc",
    readonly = "no" ]

but in the OpenNebula documentation one can read that without a
specifying a type, "disk" is assumed and I need a Xen phy: device.

The thing I need to express with OpenNebula needs to be translated  to 
something like

disk = [ 'file:/vm/udo-wn099_root.img,xvda,w',
'file:/vm/udo-wn099_swap.img,xvdb,w', 'phy:/dev/cciss/c0d0p4,xvdc,w' ]

in Xen-speak.


What do I need to specify to make use of the phy: partition located at
each of the cluster nodes?


Kind regards,
Stefan