[libvirt] virDomainAttachDevice error during disk hotplug

[Deepak C Shetty]

On 08/16/2013 07:51 PM, Daniel P. Berrange wrote:
> On Sat, Aug 10, 2013 at 05:38:20PM +0530, Deepak C Shetty wrote:
>> Hi All,
>>      I am trying to do a hotplug of a disk from VDSM (which uses
>> libvirt to get things done).
>> I hit the below error "operation failed: open disk image file
>> failed" comign from virDomainAttachDevice.
>>
>> Some background:
>>
>> 1) The qemu-img create  cmd I use (inside vdsm) to create the file
>> being hotplugged is
>>
>> /usr/bin/qemu-img create -f qcow2 -F qcow2 -b /rhev/data-center/000065de-04b8-42e2-986c-2de664708be7/11112d24-4cda-4200-8f6d-a1d8362c70fd/images/22224c45-6504-4ea1-bd24-12340017dd32/3333017d-1278-4bfb-8129-62bded257399
>> /var/run/vdsm/3333017d-1278-4bfb-8129-62bded257399' (cwd
>> /var/run/vdsm)
>>
>> I even tried using the rel. backing path instead of abs. path as below..
>>
>> /usr/bin/qemu-img create -f qcow2 -F qcow2 -b ../../../rhev/data-center/000065de-04b8-42e2-986c-2de664708be7/11112d24-4cda-4200-8f6d-a1d8362c70fd/images/22224c45-6504-4ea1-bd24-12340017dd32/3333017d-1278-4bfb-8129-62bded257399
>> /var/run/vdsm/3333017d-1278-4bfb-8129-62bded257399' (cwd
>> /var/run/vdsm)
>>
>> but hit the same error during hotplug operation
>>
>> 2) qemu-img info /var/run/vdsm/3333017d-1278-4bfb-8129-62bded257399
>> image: /var/run/vdsm/3333017d-1278-4bfb-8129-62bded257399
>> file format: qcow2
>> virtual size: 3.8G (4096000000 bytes)
>> disk size: 196K
>> cluster_size: 65536
>> backing file: /rhev/data-center/000065de-04b8-42e2-986c-2de664708be7/11112d24-4cda-4200-8f6d-a1d8362c70fd/images/22224c45-6504-4ea1-bd24-12340017dd32/3333017d-1278-4bfb-8129-62bded257399
>> backing file format: qcow2
> What does this show
>
>     qemu-img info  /rhev/data-center/000065de-04b8-42e2-986c-2de664708be7/11112d24-4cda-4200-8f6d-a1d8362c70fd/images/22224c45-6504-4ea1-bd24-12340017dd32/3333017d-1278-4bfb-8129-62bded257399
>
> ?

[root at vdsm_tsm_int_f19 vdsm]# qemu-img info 
/rhev/data-center/000065de-04b8-42e2-986c-2de664708be7/11112d24-4cda-4200-8f6d-a1d8362c70fd/images/22224c45-6504-4ea1-bd24-12340017dd32/3333017d-1278-4bfb-8129-62bded257399
image: 
/rhev/data-center/000065de-04b8-42e2-986c-2de664708be7/11112d24-4cda-4200-8f6d-a1d8362c70fd/images/22224c45-6504-4ea1-bd24-12340017dd32/3333017d-1278-4bfb-8129-62bded257399
file format: qcow2
virtual size: 3.8G (4096000000 bytes)
disk size: 136K
cluster_size: 65536

[root at vdsm_tsm_int_f19 vdsm]# ls -l 
/rhev/data-center/000065de-04b8-42e2-986c-2de664708be7/11112d24-4cda-4200-8f6d-a1d8362c70fd/images/22224c45-6504-4ea1-bd24-12340017dd32/3333017d-1278-4bfb-8129-62bded257399
-r--r-----. 1 vdsm kvm 197120 Aug 16 18:28 
/rhev/data-center/000065de-04b8-42e2-986c-2de664708be7/11112d24-4cda-4200-8f6d-a1d8362c70fd/images/22224c45-6504-4ea1-bd24-12340017dd32/3333017d-1278-4bfb-8129-62bded257399

thanx,
deepak

> Daniel