[ovirt-devel] Re: [EXTERNAL] Re: List of Queries related to RHV

[Nir Soffer]

On Tue, Nov 13, 2018 at 7:12 PM Suchitra Herwadkar <
suchitra.herwad...@veritas.com> wrote:

> Hi Nir
>
>
>
> In a case of recovery here are the steps we intend to do
>
> --First create an empty disk with the desired disk format ( RAW/COW)
>
> --Then upload the backup image contents within it using the image transfer
> APIs.
>
> --Attach the disk to the created VM.
>
>
>
> During the 2nd step, if it happens to be a QCOW disk, how can we upload
> the backup image contents and lay it down in a QCOW2 format. Or does the
> image transfer API for upload handles it internally ?
>
> Just wanted to ensure if we need to do anything post upload for QCOW?
>

When uploading and downloading images in 4.2 there is nothing special about
the
image format.

When downloading an image you get the image contents as stored in storage.
For
raw image this is the same data as seen by the guest. For qcow2 images, it
is the
qcow2 file contents as stored in file based storage, or the qcow2 contents
stored in
the block device with block based storage.

This is the same when uploading images back to storage, when you upload
qcow2
image the exact image you upload is stored in the underlying ovirt volume.

Note that when uploading qcow2 image, the image must have valid backing
file, matching
the backing file defined in ovirt.

If the VM disk has no snapshots and is not based on a template, there is no
backing
file, and the qcow2 image must not have a backing file.

If you upload a new snapshot to existing chain, the qcow2 image backing
file must be
the volume name of the current snapshot (a uuid).

Please see these examples for more info:
- upload disk with single volume (raw or qcow)

https://github.com/oVirt/ovirt-engine-sdk/blob/master/sdk/examples/upload_disk.py

- upload disk with multiple snaphosts

https://github.com/oVirt/ovirt-engine-sdk/blob/master/sdk/examples/upload_disk_snapshots.py

If you store the backup data in another format, or want to create one image
from multiple
qcow2 snapshots, you must prepare the image in some temporary storage using
qemu-img
(for example, qemu-img commit for merging qcow2 snaphosts), and then upload
the
qcow2 image to storage.

You can also convert raw to qcow2 or qcow2 to raw using qemu-img.

In 4.3 we will support an improved workflow, when you always download and
upload
raw guest data regardless of the underlying disk format. See the feature
page
for more info:
https://ovirt.org/develop/release-management/features/storage/incremental-backup/

Nir



>
>
> Kindly confirm.
>
>
>
> -Suchitra
>
>
>
> *From: *Nir Soffer 
> *Date: *Friday, November 2, 2018 at 8:12 PM
> *To: *Mahesh Falmari , Ryan Barry <
> rba...@redhat.com>
> *Cc: *Arik Hadas , Martin Perina ,
> "Yaniv Lavi (Dary)" , Daniel Erez ,
> "Nisan, Tal" , Pavan Chavva ,
> devel , James Olson , Navin Tah
> , Sudhakar Paulzagade <
> sudhakar.paulzag...@veritas.com>, Abhay Marode ,
> Suchitra Herwadkar , Nirmalya Sirkar <
> nirmalya.sir...@veritas.com>, Abhijeet Barve 
> *Subject: *Re: [EXTERNAL] Re: List of Queries related to RHV
>
>
>
> On Fri, Nov 2, 2018 at 3:22 PM Mahesh Falmari 
> wrote:
>
> Thanks Nir for the answers.
>
> Just a follow up question to your answer on Q.3>
> [Nir] Regarding backup, I think you need to store the vm configuration at
> the time of the backup regardless of having a version or not. The amount of
> data is very small.
>
> [Mahesh] We are looking for VM version information to be stored during
> backup for different reasons. One of the reason is in order to determine
> the compatibility of VM backed up from the latest version of RHV server and
> getting restored to the older versions.
>
>
>
> Trying to restore VM on older version sound fragile. Even if this works,
>
> I don't think we test such scenarios, so this is likely to break in future
>
> versions.
>
>
>
> Also, when you say vm configuration, what specific APIs could be leveraged
> to get it?
> Still looking for answer to whether VM version information will be
> available or not.
>
>
>
> I hope that Ryan to help with this.
>
>
>
>
>
> Thanks & Regards,
> Mahesh Falmari
>
>
>
> *From:* Nir Soffer 
> *Sent:* Friday, November 2, 2018 1:01 AM
> *To:* Mahesh Falmari ; Arik Hadas <
> aha...@redhat.com>; Martin Perina 
> *Cc:* Yaniv Lavi (Dary) ; Daniel Erez ;
> Nisan, Tal ; Pavan Chavva ; devel <
> devel@ovirt.org>; James Olson ; Navin Tah <
> navin@veritas.com>; Sudhakar Paulzagade <
> sudhakar.paulzag...@veritas.com>; Abhay Marode ;
> Suchitra Herwadkar ; Nirmalya Sirkar <
> nirmalya.sir...@veritas.com>; Abhijeet Barve 
> *Subject:* Re: [EXTERNAL] Re: List of Queries related to RHV
>
>
>
> On Wed, Oct 17, 2018 at 5:03 PM Mahesh Falmari 
> wrote:
>
> Thanks for the prompt response on these queries. We have few follow-up
> queries mentioned inline.
>
>
>
> Thanks & Regards,
> Mahesh Falmari
>
>
>
> *From:* Yaniv Lavi 
> *Sent:* Tuesday, October 16, 2018 7:19 PM
> *To:* Mahesh Falmari 
> *Cc:* Nir Soffer ; Erez, Daniel ;
> Tal Nisan ; Pavan Chavva ; devel 

[ovirt-devel] Re: [EXTERNAL] Re: List of Queries related to RHV

[Suchitra Herwadkar]

Hi Nir

In a case of recovery here are the steps we intend to do
--First create an empty disk with the desired disk format ( RAW/COW)
--Then upload the backup image contents within it using the image transfer APIs.
--Attach the disk to the created VM.

During the 2nd step, if it happens to be a QCOW disk, how can we upload the 
backup image contents and lay it down in a QCOW2 format. Or does the image 
transfer API for upload handles it internally ?
Just wanted to ensure if we need to do anything post upload for QCOW?

Kindly confirm.

-Suchitra

From: Nir Soffer 
Date: Friday, November 2, 2018 at 8:12 PM
To: Mahesh Falmari , Ryan Barry 
Cc: Arik Hadas , Martin Perina , "Yaniv 
Lavi (Dary)" , Daniel Erez , "Nisan, Tal" 
, Pavan Chavva , devel 
, James Olson , Navin Tah 
, Sudhakar Paulzagade , 
Abhay Marode , Suchitra Herwadkar 
, Nirmalya Sirkar 
, Abhijeet Barve 
Subject: Re: [EXTERNAL] Re: List of Queries related to RHV

On Fri, Nov 2, 2018 at 3:22 PM Mahesh Falmari 
mailto:mahesh.falm...@veritas.com>> wrote:
Thanks Nir for the answers.

Just a follow up question to your answer on Q.3>
[Nir] Regarding backup, I think you need to store the vm configuration at the 
time of the backup regardless of having a version or not. The amount of data is 
very small.
[Mahesh] We are looking for VM version information to be stored during backup 
for different reasons. One of the reason is in order to determine the 
compatibility of VM backed up from the latest version of RHV server and getting 
restored to the older versions.

Trying to restore VM on older version sound fragile. Even if this works,
I don't think we test such scenarios, so this is likely to break in future
versions.

Also, when you say vm configuration, what specific APIs could be leveraged to 
get it?
Still looking for answer to whether VM version information will be available or 
not.

I hope that Ryan to help with this.


Thanks & Regards,
Mahesh Falmari

From: Nir Soffer mailto:nsof...@redhat.com>>
Sent: Friday, November 2, 2018 1:01 AM
To: Mahesh Falmari 
mailto:mahesh.falm...@veritas.com>>; Arik Hadas 
mailto:aha...@redhat.com>>; Martin Perina 
mailto:mper...@redhat.com>>
Cc: Yaniv Lavi (Dary) mailto:yl...@redhat.com>>; Daniel Erez 
mailto:de...@redhat.com>>; Nisan, Tal 
mailto:tni...@redhat.com>>; Pavan Chavva 
mailto:pcha...@redhat.com>>; devel 
mailto:devel@ovirt.org>>; James Olson 
mailto:james.ol...@veritas.com>>; Navin Tah 
mailto:navin@veritas.com>>; Sudhakar Paulzagade 
mailto:sudhakar.paulzag...@veritas.com>>; 
Abhay Marode mailto:abhay.mar...@veritas.com>>; 
Suchitra Herwadkar 
mailto:suchitra.herwad...@veritas.com>>; 
Nirmalya Sirkar 
mailto:nirmalya.sir...@veritas.com>>; Abhijeet 
Barve mailto:abhijeet.ba...@veritas.com>>
Subject: Re: [EXTERNAL] Re: List of Queries related to RHV

On Wed, Oct 17, 2018 at 5:03 PM Mahesh Falmari 
mailto:mahesh.falm...@veritas.com>> wrote:
Thanks for the prompt response on these queries. We have few follow-up queries 
mentioned inline.

Thanks & Regards,
Mahesh Falmari

From: Yaniv Lavi mailto:yl...@redhat.com>>
Sent: Tuesday, October 16, 2018 7:19 PM
To: Mahesh Falmari 
mailto:mahesh.falm...@veritas.com>>
Cc: Nir Soffer mailto:nsof...@redhat.com>>; Erez, Daniel 
mailto:de...@redhat.com>>; Tal Nisan 
mailto:tni...@redhat.com>>; Pavan Chavva 
mailto:pcha...@redhat.com>>; devel 
mailto:devel@ovirt.org>>; James Olson 
mailto:james.ol...@veritas.com>>; Navin Tah 
mailto:navin@veritas.com>>; Sudhakar Paulzagade 
mailto:sudhakar.paulzag...@veritas.com>>; 
Abhay Marode mailto:abhay.mar...@veritas.com>>; 
Suchitra Herwadkar 
mailto:suchitra.herwad...@veritas.com>>; 
Nirmalya Sirkar 
mailto:nirmalya.sir...@veritas.com>>; Abhijeet 
Barve mailto:abhijeet.ba...@veritas.com>>
Subject: [EXTERNAL] Re: List of Queries related to RHV



YANIV LAVI

SENIOR TECHNICAL PRODUCT MANAGER

Red Hat Israel Ltd.

34 Jerusalem Road, Building A, 1st floor

Ra'anana, Israel 4350109

yl...@redhat.comT: 
+972-9-7692306/8272306 F: 
+972-9-7692223IM: ylavi
[Image removed by sender.]

TRIED. TESTED. TRUSTED.


@redhatnews   Red 
Hat   Red 
Hat

On Tue, Oct 16, 2018 at 4:35 PM Mahesh Falmari 
mailto:mahesh.falm...@veritas.com>> wrote:
Hi Nir,

We have few queries with respect to RHV which we would like to understand from 
you.

1. Does RHV maintains the virtual machine configuration file in back end?
Just like we have configuration files for other hypervisors like for VMware it 
is .vmx and for Hyper-V, it is .vmcx which captures most of the virtual machine 
configuration information in that. On the similar lines, does RHV also 
maintains such file? If not, what is the other way to get all the virtual 
machine configuration information from a single API?

There is a OVF storage, but this is not meant for 

[ovirt-devel] Re: [EXTERNAL] Re: List of Queries related to RHV

[Pavan Chavva]

On Fri, Nov 2, 2018 at 10:42 AM Nir Soffer  wrote:

> On Fri, Nov 2, 2018 at 3:22 PM Mahesh Falmari 
> wrote:
>
>> Thanks Nir for the answers.
>>
>> Just a follow up question to your answer on Q.3>
>> [Nir] Regarding backup, I think you need to store the vm configuration at
>> the time of the backup regardless of having a version or not. The amount of
>> data is very small.
>>
>> [Mahesh] We are looking for VM version information to be stored during
>> backup for different reasons. One of the reason is in order to determine
>> the compatibility of VM backed up from the latest version of RHV server and
>> getting restored to the older versions.
>>
>
> Trying to restore VM on older version sound fragile. Even if this works,
> I don't think we test such scenarios, so this is likely to break in future
> versions.
>
>
>> Also, when you say vm configuration, what specific APIs could be
>> leveraged to get it?
>> Still looking for answer to whether VM version information will be
>> available or not.
>>
>
> I hope that Ryan to help with this.
>

@Ryan Barry   Can you provide more feedback about this?

Thanks,
Pavan.


>
>
>>
>>
>> Thanks & Regards,
>> Mahesh Falmari
>>
>>
>>
>> *From:* Nir Soffer 
>> *Sent:* Friday, November 2, 2018 1:01 AM
>> *To:* Mahesh Falmari ; Arik Hadas <
>> aha...@redhat.com>; Martin Perina 
>> *Cc:* Yaniv Lavi (Dary) ; Daniel Erez ;
>> Nisan, Tal ; Pavan Chavva ; devel
>> ; James Olson ; Navin Tah <
>> navin@veritas.com>; Sudhakar Paulzagade <
>> sudhakar.paulzag...@veritas.com>; Abhay Marode ;
>> Suchitra Herwadkar ; Nirmalya Sirkar <
>> nirmalya.sir...@veritas.com>; Abhijeet Barve 
>> *Subject:* Re: [EXTERNAL] Re: List of Queries related to RHV
>>
>>
>>
>> On Wed, Oct 17, 2018 at 5:03 PM Mahesh Falmari <
>> mahesh.falm...@veritas.com> wrote:
>>
>> Thanks for the prompt response on these queries. We have few follow-up
>> queries mentioned inline.
>>
>>
>>
>> Thanks & Regards,
>> Mahesh Falmari
>>
>>
>>
>> *From:* Yaniv Lavi 
>> *Sent:* Tuesday, October 16, 2018 7:19 PM
>> *To:* Mahesh Falmari 
>> *Cc:* Nir Soffer ; Erez, Daniel ;
>> Tal Nisan ; Pavan Chavva ; devel <
>> devel@ovirt.org>; James Olson ; Navin Tah <
>> navin@veritas.com>; Sudhakar Paulzagade <
>> sudhakar.paulzag...@veritas.com>; Abhay Marode ;
>> Suchitra Herwadkar ; Nirmalya Sirkar <
>> nirmalya.sir...@veritas.com>; Abhijeet Barve 
>> *Subject:* [EXTERNAL] Re: List of Queries related to RHV
>>
>>
>>
>>
>> *YANIV LAVI*
>>
>> SENIOR TECHNICAL PRODUCT MANAGER
>>
>> Red Hat Israel Ltd. 
>>
>> 34 Jerusalem Road, Building A, 1st floor
>>
>> Ra'anana, Israel 4350109
>>
>> yl...@redhat.comT: +972-9-7692306/8272306 F: +972-9-7692223
>>  IM: ylavi
>>
>> 
>>
>> *TRIED. TESTED. TRUSTED.* 
>>
>> @redhatnews    Red Hat 
>>    Red Hat 
>> 
>>
>>
>>
>> On Tue, Oct 16, 2018 at 4:35 PM Mahesh Falmari <
>> mahesh.falm...@veritas.com> wrote:
>>
>> Hi Nir,
>>
>> We have few queries with respect to RHV which we would like to understand
>> from you.
>>
>>
>>
>> *1. Does RHV maintains the virtual machine configuration file in back
>> end?*
>>
>> Just like we have configuration files for other hypervisors like for
>> VMware it is .vmx and for Hyper-V, it is .vmcx which captures most of the
>> virtual machine configuration information in that. On the similar lines,
>> does RHV also maintains such file? If not, what is the other way to get all
>> the virtual machine configuration information from a single API?
>>
>>
>>
>> There is a OVF storage, but this is not meant for consumption.
>>
>>
>>
>> Right, this is only for internal use.
>>
>>
>>
>> ...
>>
>> *3. Do we have any version associated with the virtual machine?*
>>
>> Just like we have hardware version in case of VMware and virtual machine
>> version in case of Hyper-V, does RHV also associate any such version with
>> virtual machine?
>>
>>
>>
>> The HW version is based on the VM machine type.
>>
>>  [Mahesh] Can you please elaborate more on this? How simply VM machine
>> type going to determine it’s version?
>>
>>
>>
>> Arik, can you answer this?
>>
>>
>>
>> Regarding backup, I think you need to store the vm configuration at the
>> time of the
>>
>> backup regardless of having a version or not. The amount of data is very
>> small.
>>
>> *4. Is it possible to create virtual machines with QCOW2 as base disks
>> instead of RAW?*
>>
>> We would like to understand if there are any use cases customers prefer
>> creating virtual machines from QCOW2 as base disks instead of RAW ones.
>>
>>
>>
>> That is a possibility in cases of thin disk on file storage.
>>
>>   [Mahesh] Can you please elaborate more on this?
>>
>>
>>
>> Using the UI you can use qcow2 format only for thin disks on block
>> storage.
>>
>>
>>
>> Using the SDK you can also create qcow2 image on thin file based storage.
>>
>>
>>
>> You can 

[ovirt-devel] Re: [EXTERNAL] Re: List of Queries related to RHV

[Mahesh Falmari]

Thanks Nir for the answers.

Just a follow up question to your answer on Q.3>
[Nir] Regarding backup, I think you need to store the vm configuration at the 
time of the backup regardless of having a version or not. The amount of data is 
very small.
[Mahesh] We are looking for VM version information to be stored during backup 
for different reasons. One of the reason is in order to determine the 
compatibility of VM backed up from the latest version of RHV server and getting 
restored to the older versions.
Also, when you say vm configuration, what specific APIs could be leveraged to 
get it?
Still looking for answer to whether VM version information will be available or 
not.

Thanks & Regards,
Mahesh Falmari

From: Nir Soffer 
Sent: Friday, November 2, 2018 1:01 AM
To: Mahesh Falmari ; Arik Hadas 
; Martin Perina 
Cc: Yaniv Lavi (Dary) ; Daniel Erez ; 
Nisan, Tal ; Pavan Chavva ; devel 
; James Olson ; Navin Tah 
; Sudhakar Paulzagade ; 
Abhay Marode ; Suchitra Herwadkar 
; Nirmalya Sirkar 
; Abhijeet Barve 
Subject: Re: [EXTERNAL] Re: List of Queries related to RHV

On Wed, Oct 17, 2018 at 5:03 PM Mahesh Falmari 
mailto:mahesh.falm...@veritas.com>> wrote:
Thanks for the prompt response on these queries. We have few follow-up queries 
mentioned inline.

Thanks & Regards,
Mahesh Falmari

From: Yaniv Lavi mailto:yl...@redhat.com>>
Sent: Tuesday, October 16, 2018 7:19 PM
To: Mahesh Falmari 
mailto:mahesh.falm...@veritas.com>>
Cc: Nir Soffer mailto:nsof...@redhat.com>>; Erez, Daniel 
mailto:de...@redhat.com>>; Tal Nisan 
mailto:tni...@redhat.com>>; Pavan Chavva 
mailto:pcha...@redhat.com>>; devel 
mailto:devel@ovirt.org>>; James Olson 
mailto:james.ol...@veritas.com>>; Navin Tah 
mailto:navin@veritas.com>>; Sudhakar Paulzagade 
mailto:sudhakar.paulzag...@veritas.com>>; 
Abhay Marode mailto:abhay.mar...@veritas.com>>; 
Suchitra Herwadkar 
mailto:suchitra.herwad...@veritas.com>>; 
Nirmalya Sirkar 
mailto:nirmalya.sir...@veritas.com>>; Abhijeet 
Barve mailto:abhijeet.ba...@veritas.com>>
Subject: [EXTERNAL] Re: List of Queries related to RHV



YANIV LAVI

SENIOR TECHNICAL PRODUCT MANAGER

Red Hat Israel Ltd.

34 Jerusalem Road, Building A, 1st floor

Ra'anana, Israel 4350109

yl...@redhat.comT: 
+972-9-7692306/8272306 F: 
+972-9-7692223IM: ylavi
[https://www.redhat.com/files/brand/email/sig-redhat.png]

TRIED. TESTED. TRUSTED.


@redhatnews   Red 
Hat   Red 
Hat

On Tue, Oct 16, 2018 at 4:35 PM Mahesh Falmari 
mailto:mahesh.falm...@veritas.com>> wrote:
Hi Nir,

We have few queries with respect to RHV which we would like to understand from 
you.

1. Does RHV maintains the virtual machine configuration file in back end?
Just like we have configuration files for other hypervisors like for VMware it 
is .vmx and for Hyper-V, it is .vmcx which captures most of the virtual machine 
configuration information in that. On the similar lines, does RHV also 
maintains such file? If not, what is the other way to get all the virtual 
machine configuration information from a single API?

There is a OVF storage, but this is not meant for consumption.

Right, this is only for internal use.

...
3. Do we have any version associated with the virtual machine?
Just like we have hardware version in case of VMware and virtual machine 
version in case of Hyper-V, does RHV also associate any such version with 
virtual machine?

The HW version is based on the VM machine type.
 [Mahesh] Can you please elaborate more on this? How simply VM machine type 
going to determine it’s version?

Arik, can you answer this?

Regarding backup, I think you need to store the vm configuration at the time of 
the
backup regardless of having a version or not. The amount of data is very small.
4. Is it possible to create virtual machines with QCOW2 as base disks instead 
of RAW?
We would like to understand if there are any use cases customers prefer 
creating virtual machines from QCOW2 as base disks instead of RAW ones.

That is a possibility in cases of thin disk on file storage.
  [Mahesh] Can you please elaborate more on this?

Using the UI you can use qcow2 format only for thin disks on block storage.

Using the SDK you can also create qcow2 image on thin file based storage.

You can see examples here:
https://github.com/oVirt/ovirt-engine-sdk/blob/78c3d5bd14eeb93ef72ec31d775ff5c41f51a8c7/sdk/examples/upload_disk.py#L123

In 4.3 we plan to support qcow2 image format for both thin and preallocated
disks to allow change block tracking for incremental backup. See
html: 
https://github.com/oVirt/ovirt-site/blob/bc51f4a7867d9c7e3797da6da1d19e111cd2ff67/source/develop/release-management/features/storage/incremental-backup.html.md

5. RHV Deployment
What kind of deployments you have come across in the field? Does customers 
scale their 

[ovirt-devel] Re: [EXTERNAL] Re: List of Queries related to RHV

[Nir Soffer]

On Fri, Nov 2, 2018 at 3:22 PM Mahesh Falmari 
wrote:

> Thanks Nir for the answers.
>
> Just a follow up question to your answer on Q.3>
> [Nir] Regarding backup, I think you need to store the vm configuration at
> the time of the backup regardless of having a version or not. The amount of
> data is very small.
>
> [Mahesh] We are looking for VM version information to be stored during
> backup for different reasons. One of the reason is in order to determine
> the compatibility of VM backed up from the latest version of RHV server and
> getting restored to the older versions.
>

Trying to restore VM on older version sound fragile. Even if this works,
I don't think we test such scenarios, so this is likely to break in future
versions.


> Also, when you say vm configuration, what specific APIs could be leveraged
> to get it?
> Still looking for answer to whether VM version information will be
> available or not.
>

I hope that Ryan to help with this.


>
>
> Thanks & Regards,
> Mahesh Falmari
>
>
>
> *From:* Nir Soffer 
> *Sent:* Friday, November 2, 2018 1:01 AM
> *To:* Mahesh Falmari ; Arik Hadas <
> aha...@redhat.com>; Martin Perina 
> *Cc:* Yaniv Lavi (Dary) ; Daniel Erez ;
> Nisan, Tal ; Pavan Chavva ; devel <
> devel@ovirt.org>; James Olson ; Navin Tah <
> navin@veritas.com>; Sudhakar Paulzagade <
> sudhakar.paulzag...@veritas.com>; Abhay Marode ;
> Suchitra Herwadkar ; Nirmalya Sirkar <
> nirmalya.sir...@veritas.com>; Abhijeet Barve 
> *Subject:* Re: [EXTERNAL] Re: List of Queries related to RHV
>
>
>
> On Wed, Oct 17, 2018 at 5:03 PM Mahesh Falmari 
> wrote:
>
> Thanks for the prompt response on these queries. We have few follow-up
> queries mentioned inline.
>
>
>
> Thanks & Regards,
> Mahesh Falmari
>
>
>
> *From:* Yaniv Lavi 
> *Sent:* Tuesday, October 16, 2018 7:19 PM
> *To:* Mahesh Falmari 
> *Cc:* Nir Soffer ; Erez, Daniel ;
> Tal Nisan ; Pavan Chavva ; devel <
> devel@ovirt.org>; James Olson ; Navin Tah <
> navin@veritas.com>; Sudhakar Paulzagade <
> sudhakar.paulzag...@veritas.com>; Abhay Marode ;
> Suchitra Herwadkar ; Nirmalya Sirkar <
> nirmalya.sir...@veritas.com>; Abhijeet Barve 
> *Subject:* [EXTERNAL] Re: List of Queries related to RHV
>
>
>
>
> *YANIV LAVI*
>
> SENIOR TECHNICAL PRODUCT MANAGER
>
> Red Hat Israel Ltd. 
>
> 34 Jerusalem Road, Building A, 1st floor
>
> Ra'anana, Israel 4350109
>
> yl...@redhat.comT: +972-9-7692306/8272306 F: +972-9-7692223
>  IM: ylavi
>
> 
>
> *TRIED. TESTED. TRUSTED.* 
>
> @redhatnews    Red Hat 
>    Red Hat 
> 
>
>
>
> On Tue, Oct 16, 2018 at 4:35 PM Mahesh Falmari 
> wrote:
>
> Hi Nir,
>
> We have few queries with respect to RHV which we would like to understand
> from you.
>
>
>
> *1. Does RHV maintains the virtual machine configuration file in back end?*
>
> Just like we have configuration files for other hypervisors like for
> VMware it is .vmx and for Hyper-V, it is .vmcx which captures most of the
> virtual machine configuration information in that. On the similar lines,
> does RHV also maintains such file? If not, what is the other way to get all
> the virtual machine configuration information from a single API?
>
>
>
> There is a OVF storage, but this is not meant for consumption.
>
>
>
> Right, this is only for internal use.
>
>
>
> ...
>
> *3. Do we have any version associated with the virtual machine?*
>
> Just like we have hardware version in case of VMware and virtual machine
> version in case of Hyper-V, does RHV also associate any such version with
> virtual machine?
>
>
>
> The HW version is based on the VM machine type.
>
>  [Mahesh] Can you please elaborate more on this? How simply VM machine
> type going to determine it’s version?
>
>
>
> Arik, can you answer this?
>
>
>
> Regarding backup, I think you need to store the vm configuration at the
> time of the
>
> backup regardless of having a version or not. The amount of data is very
> small.
>
> *4. Is it possible to create virtual machines with QCOW2 as base disks
> instead of RAW?*
>
> We would like to understand if there are any use cases customers prefer
> creating virtual machines from QCOW2 as base disks instead of RAW ones.
>
>
>
> That is a possibility in cases of thin disk on file storage.
>
>   [Mahesh] Can you please elaborate more on this?
>
>
>
> Using the UI you can use qcow2 format only for thin disks on block storage.
>
>
>
> Using the SDK you can also create qcow2 image on thin file based storage.
>
>
>
> You can see examples here:
>
>
> https://github.com/oVirt/ovirt-engine-sdk/blob/78c3d5bd14eeb93ef72ec31d775ff5c41f51a8c7/sdk/examples/upload_disk.py#L123
>
>
>
> In 4.3 we plan to support qcow2 image format for both thin and preallocated
>
> disks to allow change block tracking for incremental backup. See
>
> html:
> 

[ovirt-devel] Re: [EXTERNAL] Re: List of Queries related to RHV

[Nir Soffer]

On Wed, Oct 17, 2018 at 5:03 PM Mahesh Falmari 
wrote:

> Thanks for the prompt response on these queries. We have few follow-up
> queries mentioned inline.
>
>
>
> Thanks & Regards,
> Mahesh Falmari
>
>
>
> *From:* Yaniv Lavi 
> *Sent:* Tuesday, October 16, 2018 7:19 PM
> *To:* Mahesh Falmari 
> *Cc:* Nir Soffer ; Erez, Daniel ;
> Tal Nisan ; Pavan Chavva ; devel <
> devel@ovirt.org>; James Olson ; Navin Tah <
> navin@veritas.com>; Sudhakar Paulzagade <
> sudhakar.paulzag...@veritas.com>; Abhay Marode ;
> Suchitra Herwadkar ; Nirmalya Sirkar <
> nirmalya.sir...@veritas.com>; Abhijeet Barve 
> *Subject:* [EXTERNAL] Re: List of Queries related to RHV
>
>
>
>
> *YANIV LAVI*
>
> SENIOR TECHNICAL PRODUCT MANAGER
>
> Red Hat Israel Ltd. 
>
> 34 Jerusalem Road, Building A, 1st floor
>
> Ra'anana, Israel 4350109
>
> yl...@redhat.comT: +972-9-7692306/8272306 F: +972-9-7692223
>  IM: ylavi
>
> 
>
> *TRIED. TESTED. TRUSTED.* 
>
> @redhatnews    Red Hat 
>    Red Hat 
> 
>
>
>
> On Tue, Oct 16, 2018 at 4:35 PM Mahesh Falmari 
> wrote:
>
> Hi Nir,
>
> We have few queries with respect to RHV which we would like to understand
> from you.
>
>
>
> *1. Does RHV maintains the virtual machine configuration file in back end?*
>
> Just like we have configuration files for other hypervisors like for
> VMware it is .vmx and for Hyper-V, it is .vmcx which captures most of the
> virtual machine configuration information in that. On the similar lines,
> does RHV also maintains such file? If not, what is the other way to get all
> the virtual machine configuration information from a single API?
>
>
>
> There is a OVF storage, but this is not meant for consumption.
>

Right, this is only for internal use.

...

> *3. Do we have any version associated with the virtual machine?*
>
> Just like we have hardware version in case of VMware and virtual machine
> version in case of Hyper-V, does RHV also associate any such version with
> virtual machine?
>
>
>
> The HW version is based on the VM machine type.
>
>  [Mahesh] Can you please elaborate more on this? How simply VM machine
> type going to determine it’s version?
>

Arik, can you answer this?

Regarding backup, I think you need to store the vm configuration at the
time of the
backup regardless of having a version or not. The amount of data is very
small.

> *4. Is it possible to create virtual machines with QCOW2 as base disks
> instead of RAW?*
>
> We would like to understand if there are any use cases customers prefer
> creating virtual machines from QCOW2 as base disks instead of RAW ones.
>
>
>
> That is a possibility in cases of thin disk on file storage.
>
>   [Mahesh] Can you please elaborate more on this?
>

Using the UI you can use qcow2 format only for thin disks on block storage.

Using the SDK you can also create qcow2 image on thin file based storage.

You can see examples here:
https://github.com/oVirt/ovirt-engine-sdk/blob/78c3d5bd14eeb93ef72ec31d775ff5c41f51a8c7/sdk/examples/upload_disk.py#L123

In 4.3 we plan to support qcow2 image format for both thin and preallocated
disks to allow change block tracking for incremental backup. See
html:
https://github.com/oVirt/ovirt-site/blob/bc51f4a7867d9c7e3797da6da1d19e111cd2ff67/source/develop/release-management/features/storage/incremental-backup.html.md

>
>
> *5. RHV Deployment*
>
> What kind of deployments you have come across in the field? Does customers
> scale their infrastructure by adding more datacenters/clusters/nodes or
> they add more RHV managers? What scenarios trigger having more than one RHV
> manager?
>
>
>
> We are all kind with oVirt. I depends on the use case.
>

I don't know about any stats from users, but the general idea is:

- one engine
- 1 or more DCs
- 1 or more storage domains in a DC
- 1 or more clusters per DCs
- 1 or more hosts per cluster

The theoretical limit is 2000 hosts per DC (limited by sanlock), but the
practical
limit is much lower. I don't think we have setups with more than 200 hosts.

Martin, do you have more info on this?

> *6. Image transfer*
>
> We are trying to download disk chunks using multiple threads to improve
> performance of reading data from RHV. Downloading 2 disk chunks
> simultaneously via threads should take approximately the same time.
>
> This is much more complicated to calculate.

> But from our observations this takes roughly 1.5 times.
>
>
It sounds like a reasonable speed up.

Can RHVM server requests in parallel,
>
>
Yes


> if so are there any settings that need to be tweaked?
>
>
We don't have any settings related to concurrency.

> Here is an example:
> Request 1 for chunk 1 from thread 1, Range: bytes=0-1023
> Request 2 for chunk 2 from thread 2, Range: bytes=1024-2047
> Takes roughly 1.5 seconds, whereas a single request would take 1 second.
> Expecting it to 

[ovirt-devel] Re: [EXTERNAL] Re: List of Queries related to RHV

[Suchitra Herwadkar]

Hi Pavan

Can someone from RH technical team could join today’s call? We can go over the 
pending questions outlined here?

Thanks
Suchitra


From: Pavan Chavva 
Date: Saturday, October 20, 2018 at 1:18 AM
To: "devel@ovirt.org" 
Cc: "Yaniv Lavi (Dary)" , Nir Soffer , 
Daniel Erez , Tal Nisan , James Olson 
, Navin Tah , Sudhakar 
Paulzagade , Abhay Marode 
, Suchitra Herwadkar 
, Nirmalya Sirkar 
, Abhijeet Barve , 
Mahesh Falmari 
Subject: Re: [EXTERNAL] Re: List of Queries related to RHV

Bumping this thread as the last update from Veritas did not reflect in OVirt 
Devel list.
Best,
Pavan.

On Wed, Oct 17, 2018 at 10:03 AM Mahesh Falmari 
mailto:mahesh.falm...@veritas.com>> wrote:
Thanks for the prompt response on these queries. We have few follow-up queries 
mentioned inline.

Thanks & Regards,
Mahesh Falmari

From: Yaniv Lavi mailto:yl...@redhat.com>>
Sent: Tuesday, October 16, 2018 7:19 PM
To: Mahesh Falmari 
mailto:mahesh.falm...@veritas.com>>
Cc: Nir Soffer mailto:nsof...@redhat.com>>; Erez, Daniel 
mailto:de...@redhat.com>>; Tal Nisan 
mailto:tni...@redhat.com>>; Pavan Chavva 
mailto:pcha...@redhat.com>>; devel 
mailto:devel@ovirt.org>>; James Olson 
mailto:james.ol...@veritas.com>>; Navin Tah 
mailto:navin@veritas.com>>; Sudhakar Paulzagade 
mailto:sudhakar.paulzag...@veritas.com>>; 
Abhay Marode mailto:abhay.mar...@veritas.com>>; 
Suchitra Herwadkar 
mailto:suchitra.herwad...@veritas.com>>; 
Nirmalya Sirkar 
mailto:nirmalya.sir...@veritas.com>>; Abhijeet 
Barve mailto:abhijeet.ba...@veritas.com>>
Subject: [EXTERNAL] Re: List of Queries related to RHV



YANIV LAVI

SENIOR TECHNICAL PRODUCT MANAGER

Red Hat Israel Ltd.

34 Jerusalem Road, Building A, 1st floor

Ra'anana, Israel 4350109

yl...@redhat.comT: 
+972-9-7692306/8272306 F: 
+972-9-7692223IM: ylavi
[Image removed by sender.]

TRIED. TESTED. TRUSTED.


@redhatnews   Red 
Hat   Red 
Hat

On Tue, Oct 16, 2018 at 4:35 PM Mahesh Falmari 
mailto:mahesh.falm...@veritas.com>> wrote:
Hi Nir,

We have few queries with respect to RHV which we would like to understand from 
you.

1. Does RHV maintains the virtual machine configuration file in back end?
Just like we have configuration files for other hypervisors like for VMware it 
is .vmx and for Hyper-V, it is .vmcx which captures most of the virtual machine 
configuration information in that. On the similar lines, does RHV also 
maintains such file? If not, what is the other way to get all the virtual 
machine configuration information from a single API?

There is a OVF storage, but this is not meant for consumption.
Please follow the first section in:
https://ovirt.org/develop/release-management/features/storage/backup-restore-disk-snapshots/
This explains how to use the API to get a OVF for a VM.


2. Is VM UUID the only way to uniquely identify virtual machine in the RHV 
infrastructure?
What we understand is that VM UUID is the way to identify virtual machine 
uniquely in the RHV infrastructure. Would like to know any other way than this?

UUID is the way to do this.


3. Do we have any version associated with the virtual machine?
Just like we have hardware version in case of VMware and virtual machine 
version in case of Hyper-V, does RHV also associate any such version with 
virtual machine?

The HW version is based on the VM machine type.
 [Mahesh] Can you please elaborate more on this? How simply VM machine type 
going to determine it’s version?

4. Is it possible to create virtual machines with QCOW2 as base disks instead 
of RAW?
We would like to understand if there are any use cases customers prefer 
creating virtual machines from QCOW2 as base disks instead of RAW ones.

That is a possibility in cases of thin disk on file storage.
  [Mahesh] Can you please elaborate more on this?

5. RHV Deployment
What kind of deployments you have come across in the field? Does customers 
scale their infrastructure by adding more datacenters/clusters/nodes or they 
add more RHV managers? What scenarios trigger having more than one RHV manager?

We are all kind with oVirt. I depends on the use case.


6. Image transfer
We are trying to download disk chunks using multiple threads to improve 
performance of reading data from RHV. Downloading 2 disk chunks simultaneously 
via threads should take approximately the same time. But from our observations 
this takes roughly 1.5 times.
Can RHVM server requests in parallel, if so are there any settings that need to 
be tweaked?
Here is an example:
Request 1 for chunk 1 from thread 1, Range: bytes=0-1023
Request 2 for chunk 2 from thread 2, Range: bytes=1024-2047
Takes roughly 1.5 seconds, whereas a single request would take 1 second. 
Expecting it to take just around 1 second.
[Mahesh] Seeking response to this query.
7. Free and Thaw operation