[ovirt-devel] Interacting with VDSM storage without oVirt Engine

[Hayley Swimelar]

On 06/01/2016 06:41 AM, Allon Mureinik wrote:
> What's the end goal of this? Why would you want something the management
> system (=engine) is not aware of?

The end goal is to integrate with the engine as well.

If working on the engine component at the same time as VDSM is 
require/preferred, I can discuss it with the other developers I am 
working with on this project.

>
> On Tue, May 31, 2016 at 7:25 PM, Hayley Swimelar <hayley at linbit.com> wrote:
>
>>
>>
>> On 05/31/2016 08:25 AM, Yaniv Dary wrote:
>>
>>> Can you explain the use case? What are you trying to use VDSM for?
>>> The API you want to use is internal and can break without notice.
>>>
>>
>> Hi Yaniv,
>>
>> I'm working to to integrate DRBD storage into VDSM.
>>
>> It will be a new type of storage domain, so I can't use the GUI since the
>> engine component won't be aware of it as far as I can tell.
>>
>> The current plan is to have another developer on our end make changes to
>> the Engine once the VDSM side is working.
>>
>>
>>
>>> Yaniv Dary
>>> Technical Product Manager
>>> Red Hat Israel Ltd.
>>> 34 Jerusalem Road
>>> Building A, 4th floor
>>> Ra'anana, Israel 4350109
>>>
>>> Tel : +972 (9) 7692306
>>>         8272306
>>> Email: ydary at redhat.com
>>> IRC : ydary
>>>
>>>
>>> On Wed, May 25, 2016 at 8:29 PM, Hayley Swimelar <hayley at linbit.com>
>>> wrote:
>>>
>>>
>>>>
>>>> On 05/25/2016 02:00 AM, Martin Sivak wrote:
>>>>
>>>> Hi,
>>>>>
>>>>> I do not remember exacly, but you might check the source code of
>>>>> hosted engine's VdsmBackend where we do that too.
>>>>>
>>>>>
>>>>>
>>>>> https://gerrit.ovirt.org/gitweb?p=ovirt-hosted-engine-ha.git;a=blob;f=ovirt_hosted_engine_ha/lib/storage_backends.py;h=f2fbdc43d0e4afd7539a3a1de75de0cb07bdca9d;hb=a012f184584af20d3dba8038d73b8d9b447af7b3
>>>>>
>>>>> I think you are missing the prepareImage call.
>>>>>
>>>>>
>>>> I think that prepareImage is probably the missing piece to this; however,
>>>> it seems that the hosted engine's create_volume method with calls
>>>> _get_volume_path which calls prepareImage.
>>>>
>>>> vdsClient's prepareImage command takes a volume UUID as an agrument I've
>>>> tried passing the new UUID I created for the createVolume command, the
>>>> UUID
>>>> returned from that command, and a fresh UUID. All of these return the
>>>> same
>>>> error: Volume does not exist
>>>>
>>>> I've also tried manually creating the image directory under the storage
>>>> domain directory with the same results for all commands.
>>>>
>>>>
>>>>
>>>> Regards
>>>>>
>>>>> --
>>>>> Martin Sivak
>>>>> SLA / oVirt
>>>>>
>>>>> On Wed, May 25, 2016 at 1:44 AM, Hayley Swimelar <hayley at linbit.com>
>>>>> wrote:
>>>>>
>>>>> Hello all,
>>>>>>
>>>>>> Like the title says, I need to work with VDSM's storage layer without
>>>>>> involving the engine.
>>>>>>
>>>>>> Presently, I'm testing this with NFS domains and have been able to use
>>>>>> vdsClient to create, attach, and activate a new storage domain, but I
>>>>>> have
>>>>>> not been able to create a new image or volume.
>>>>>>
>>>>>> Here are the commands I ran to get to this step, starting with a nfs
>>>>>> volume
>>>>>> already mounted on the machine I ran the commands on.
>>>>>>
>>>>>> ----
>>>>>> vdsClient -s host_name createStorageDomain 1
>>>>>> 97338d5c-9b6f-1859-b827-e977ed082e53 cli_domain storage_server:/data
>>>>>>
>>>>>> vdsClient -s host_name attachStorageDomain
>>>>>> 97338d5c-9b6f-1859-b827-e977ed082e53
>>>>>> 00000001-0001-0001-0001-00000000033c
>>>>>>
>>>>>> vdsClient -s host_name activateStorageDomain
>>>>>> 97338d5c-9b6f-1859-b827-e977ed082e53
>>>>>> 00000001-0001-0001-0001-00000000033c
>>>>>>
>>>>>> vdsClient -s frodo createVolume 97338d5c-9b6f-1859-b827-e977ed082e53
>>>>>> 00000001-0001-0001-0001-00000000033c
>>>>>> 0288f410-71f1-4b7d-bdb7-e815a93e34ef
>>>>>> 53690000000 5 1 2 96d7726c-6969-40a5-84bd-0925496b6051 cli_volume
>>>>>> ----
>>>>>>
>>>>>> The last command outputs a new UUID, but there is nothing under
>>>>>>
>>>>>>
>>>>>> /rhev/data-center/00000001-0001-0001-0001-00000000033c/97338d5c-9b6f-1859-b827-e977ed082e53/images/
>>>>>> directory.
>>>>>>
>>>>>> If I pass createVolume an existing image/storage domain UUID, the
>>>>>> command
>>>>>> still outputs a new UUID, but nothing changes under the images
>>>>>> directory.
>>>>>>
>>>>>> Is there a step that I am missing somewhere in this process?
>>>>>>
>>>>>> --
>>>>>> Hayley Swimelar
>>>>>> LINBIT | Keeping the Digital World Running
>>>>>> DRBD — Corosync — Pacemaker
>>>>>> +1-503-573-1262 x212
>>>>>> _______________________________________________
>>>>>> Devel mailing list
>>>>>> Devel at ovirt.org
>>>>>> http://lists.ovirt.org/mailman/listinfo/devel
>>>>>>
>>>>>>
>>>>> --
>>>> Hayley Swimelar
>>>> LINBIT | Keeping the Digital World Running
>>>> DRBD — Corosync — Pacemaker
>>>> +1-503-573-1262 x212
>>>> _______________________________________________
>>>> Devel mailing list
>>>> Devel at ovirt.org
>>>> http://lists.ovirt.org/mailman/listinfo/devel
>>>>
>>>>
>>>
>> --
>> Hayley Swimelar
>> LINBIT | Keeping the Digital World Running
>> DRBD — Corosync — Pacemaker
>> +1-503-573-1262 x212
>> _______________________________________________
>> Devel mailing list
>> Devel at ovirt.org
>> http://lists.ovirt.org/mailman/listinfo/devel
>>
>>
>>
>

-- 
Hayley Swimelar
LINBIT | Keeping the Digital World Running
DRBD — Corosync — Pacemaker
+1-503-573-1262 x212