5:34 p.m.
On 01/18/2016 02:49 PM, Algirdas Žemaitis wrote:
Hello,
I was playing with Ovirt API/python-sdk for a week or so and stuck in
one from first sight simple yet unsolvable spot…
Ovirt web GUI has option to clone VM from snapshot, to new(other)
storage domain. Is it possible to do so with API ?
The point is, I’m using backup script (already modified a lot of it to
suit our needs), once it is cloning from snapshot into new VM, it will
use same storage, and causing a lot of load on already stressed domain,
idea is to create VM (allocate disk before exporting it as backup) on
other storage domain, in this way significantly reducing impact on live
storage domain. What do you think ?
Original : https://github.com/wefixit-AT/oVirtBackup
Thank you for your time, and sorry for reaching directly, Ovirt lacks
for an forum or something similar… or I just couldn’t find it…
I'm adding the users(a)ovirt.org list, there is where you can send your
questions.
In order to clone a VM from an snapshot you have to use the "add"
operation of the "vms" service, passing as a parameter a "vm" object
that contains the identifier of the snapshot and the explicit mapping of
disk to storage domain. In XML it should look like this:
---8<---
<vm>
<name>myclone</name>
<cluster>
<name>mycluster</name>
</cluster>
<!-- This is how you indicate what snapshot to clone: -->
<snapshots>
<snapshot id="266742a5-6a65-483c-816d-d2ce49746680"/>
</snapshots>
<!-- This is how you indicate how to map disks to storage
domains. -->
<disks>
<disk>
<image_id>8d4bd566-6c86-4592-a4a7-912dbf93c298</image_id>
<storage_domains>
<storage_domain id="9cb6cb0a-cf1d-41c2-92ca-5a6d665649c9"/>
</storage_domains>
</disk>
</disks>
</vm>
--->8---
With the Python SDK it should look like this:
---8<---
# Find the VM:
vm = api.vms.get(name="myvm")
# Find the snapshot:
snapshot = None
for current in vm.snapshots.list():
if current.get_description() == 'mysnap':
snapshot = current
break # Should probably end here, with an error.
# Find the image identifiers of the disks of the snapshot, as
# we need them in order to explicitly indicate that we want
# them created in a different storage domain:
disk_ids = []
for current in snapshot.disks.list():
disk_ids.append(current.get_id())
# Find the storage domain where the disks should be created:
sd = api.storagedomains.get(name="yourdata")
# Prepare the list of disks for the operation to create the
# snapshot,explicitly indicating for each of them the storage
# domain where it should be created:
disk_list = []
for disk_id in disk_ids:
disk = params.Disk(
image_id=disk_id,
storage_domains=params.StorageDomains(
storage_domain=[
params.StorageDomain(
id=sd.get_id(),
),
],
),
)
disk_list.append(disk)
# Create the VM from the snapshot:
api.vms.add(
params.VM(
name="myclone",
cluster=params.Cluster(name="mycluster"),
snapshots=params.Snapshots(
snapshot=[
params.Snapshot(
id=snapshot.get_id(),
),
],
),
disks=params.Disks(
disk=disk_list,
),
)
)
--->8---
This should work for you.
However, I have to say that I find a bit strange that we use the
"image_id" attribute as the key of the disk in this case, instead of
just the "id". Allon, do you know if this is on purpose? I mean, when we
clone a VM from a template we use do like this:
<disk id="the_key">
...
</disk>
But in this case we do like this:
<disk>
<image_id>the_key</image_id>
...
</disk>
Is there any reason for these two different ways to specify the
identifier of the disk?
--
Dirección Comercial: C/Jose Bardasano Baos, 9, Edif. Gorbea 3, planta
3ºD, 28016 Madrid, Spain
Inscrita en el Reg. Mercantil de Madrid – C.I.F. B82657941 - Red Hat S.L.