Re: [Users] oVirt support for backup/restore

[Ayal Baron]

- Original Message -
> sön 2013-04-21 klockan 08:42 -0400 skrev Ayal Baron:
> 
> 
> 
> - Original Message -
> > On 04/19/2013 11:46 AM, Gianluca Cecchi wrote:
> > > On Fri, Apr 19, 2013 at 9:58 AM, Itamar Heim wrote:
> > >
> > >>
> > >> qemu-guest-agent isn't ovirt/rhev-guest-agent.
> > >> now that qemu started their own guest agent, ovirt/rhev-guest-agent
> > >> isn't
> > >> used for things covered by the qemu-guest-agent.
> > >
> > > Ah, ok.
> > > SO after reading
> > > http://wiki.libvirt.org/page/Qemu_guest_agent
> > > some questions
> > >
> > > can we use ootb qemu-guest-agent with ovirt 3.2.1 if we have for
> > > example a CentOS 6 guest (with qemu-guest-agent-0.12.1.2-2.355)?
> > > Does oVirt create a virtio-serial port to communicate with libvit and
> > > does it use libvirt with any options to quiesce  fs on guest?
> >
> > iirc, it should work - testing/feedback would be welcome.
> 
> I believe vdsm does not create the virtio-serial port when starting the VM,
> so you'd have to modify this behaviour with hooks [1].
> Once you do that, whenever you create a live snapshot vdsm will notify
> libvirt to quiesce first.
> Note that afaik, quiesce in qemu-ga is only supported for Linux guests.
> 
> 
> Really cool to hear how things are progressing! The qemu-ga quiesces what
> exactly? The guest filesystem? What about potential applications that might

Yes, it quiesces xfs/ext3/ext4 (I don't recall wrt btrfs) file systems.

> be running inside the guest? Can you call live snapshots of a linux guest
> "Application Consistent"?

Linux has no such infrastructure atm.  There are upstream patches for qemu-ga 
to support calling hooks before and after quiesce to allow users to freeze 
their apps so that the snapshot would be application consistent.  This will 
require users to place their scripts inside the guest of course.

> 
> The good thing about Microsoft VSS is that MS applications are registered to
> VSS so that when you trigger VSS to quiece, all of the other applications
> are told to pause as well.

Indeed, there have been many discussions around this and there is a lot of 
interest around this topic, but I haven't seen any accepted solution as of yet.

> 
> /Karli
> 
> 
> 
> VSS quiesce support patches have been submitted, but I'm not sure what the
> status is there yet.
> 
> [1] Hooks preso: http://www.ovirt.org/File:OVirt-hooks-netapp-jan2013.odp
> 
> >
> > >
> > > Can one use as an alternative the command fsfreeze in CentOS 6.4 guest
> > > (even if in tech preview) as in :
> > > https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Technical_Notes/storage.html
> > >
> >
> > what i remember is that it supposed to be pluggable/configurable for you
> > to run the relevant commands you want.
> > ayal may remember better
> >
> ___
> Users mailing list
> Users@ovirt.org
> http://lists.ovirt.org/mailman/listinfo/users
> 
> 
> --
> 
> Med Vänliga Hälsningar
> ---
> Karli Sjöberg
> Swedish University of Agricultural Sciences
> Box 7079 (Visiting Address Kronåsvägen 8)
> S-750 07 Uppsala, Sweden
> Phone:  +46-(0)18-67 15 66
> karli.sjob...@slu.se
> 
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

Re: [Users] oVirt support for backup/restore

[Karli Sjöberg]

sön 2013-04-21 klockan 08:42 -0400 skrev Ayal Baron:



- Original Message -
> On 04/19/2013 11:46 AM, Gianluca Cecchi wrote:
> > On Fri, Apr 19, 2013 at 9:58 AM, Itamar Heim wrote:
> >
> >>
> >> qemu-guest-agent isn't ovirt/rhev-guest-agent.
> >> now that qemu started their own guest agent, ovirt/rhev-guest-agent isn't
> >> used for things covered by the qemu-guest-agent.
> >
> > Ah, ok.
> > SO after reading
> > http://wiki.libvirt.org/page/Qemu_guest_agent
> > some questions
> >
> > can we use ootb qemu-guest-agent with ovirt 3.2.1 if we have for
> > example a CentOS 6 guest (with qemu-guest-agent-0.12.1.2-2.355)?
> > Does oVirt create a virtio-serial port to communicate with libvit and
> > does it use libvirt with any options to quiesce  fs on guest?
>
> iirc, it should work - testing/feedback would be welcome.

I believe vdsm does not create the virtio-serial port when starting the VM, so 
you'd have to modify this behaviour with hooks [1].
Once you do that, whenever you create a live snapshot vdsm will notify libvirt 
to quiesce first.
Note that afaik, quiesce in qemu-ga is only supported for Linux guests.


Really cool to hear how things are progressing! The qemu-ga quiesces what 
exactly? The guest filesystem? What about potential applications that might be 
running inside the guest? Can you call live snapshots of a linux guest 
"Application Consistent"?

The good thing about Microsoft VSS is that MS applications are registered to 
VSS so that when you trigger VSS to quiece, all of the other applications are 
told to pause as well.

/Karli



VSS quiesce support patches have been submitted, but I'm not sure what the 
status is there yet.

[1] Hooks preso: http://www.ovirt.org/File:OVirt-hooks-netapp-jan2013.odp

>
> >
> > Can one use as an alternative the command fsfreeze in CentOS 6.4 guest
> > (even if in tech preview) as in :
> > https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Technical_Notes/storage.html
> >
>
> what i remember is that it supposed to be pluggable/configurable for you
> to run the relevant commands you want.
> ayal may remember better
>
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users


--

Med Vänliga Hälsningar
---
Karli Sjöberg
Swedish University of Agricultural Sciences
Box 7079 (Visiting Address Kronåsvägen 8)
S-750 07 Uppsala, Sweden
Phone:  +46-(0)18-67 15 66
karli.sjob...@slu.se
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

Re: [Users] oVirt support for backup/restore

[Ayal Baron]

- Original Message -
> On 04/19/2013 11:46 AM, Gianluca Cecchi wrote:
> > On Fri, Apr 19, 2013 at 9:58 AM, Itamar Heim wrote:
> >
> >>
> >> qemu-guest-agent isn't ovirt/rhev-guest-agent.
> >> now that qemu started their own guest agent, ovirt/rhev-guest-agent isn't
> >> used for things covered by the qemu-guest-agent.
> >
> > Ah, ok.
> > SO after reading
> > http://wiki.libvirt.org/page/Qemu_guest_agent
> > some questions
> >
> > can we use ootb qemu-guest-agent with ovirt 3.2.1 if we have for
> > example a CentOS 6 guest (with qemu-guest-agent-0.12.1.2-2.355)?
> > Does oVirt create a virtio-serial port to communicate with libvit and
> > does it use libvirt with any options to quiesce  fs on guest?
> 
> iirc, it should work - testing/feedback would be welcome.

I believe vdsm does not create the virtio-serial port when starting the VM, so 
you'd have to modify this behaviour with hooks [1].
Once you do that, whenever you create a live snapshot vdsm will notify libvirt 
to quiesce first.
Note that afaik, quiesce in qemu-ga is only supported for Linux guests.  VSS 
quiesce support patches have been submitted, but I'm not sure what the status 
is there yet. 

[1] Hooks preso: http://www.ovirt.org/File:OVirt-hooks-netapp-jan2013.odp

> 
> >
> > Can one use as an alternative the command fsfreeze in CentOS 6.4 guest
> > (even if in tech preview) as in :
> > https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Technical_Notes/storage.html
> >
> 
> what i remember is that it supposed to be pluggable/configurable for you
> to run the relevant commands you want.
> ayal may remember better
> 
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

Re: [Users] oVirt support for backup/restore

[Itamar Heim]

On 04/19/2013 11:46 AM, Gianluca Cecchi wrote:

On Fri, Apr 19, 2013 at 9:58 AM, Itamar Heim wrote:



qemu-guest-agent isn't ovirt/rhev-guest-agent.
now that qemu started their own guest agent, ovirt/rhev-guest-agent isn't
used for things covered by the qemu-guest-agent.


Ah, ok.
SO after reading
http://wiki.libvirt.org/page/Qemu_guest_agent
some questions

can we use ootb qemu-guest-agent with ovirt 3.2.1 if we have for
example a CentOS 6 guest (with qemu-guest-agent-0.12.1.2-2.355)?
Does oVirt create a virtio-serial port to communicate with libvit and
does it use libvirt with any options to quiesce  fs on guest?


iirc, it should work - testing/feedback would be welcome.



Can one use as an alternative the command fsfreeze in CentOS 6.4 guest
(even if in tech preview) as in :
https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Technical_Notes/storage.html



what i remember is that it supposed to be pluggable/configurable for you 
to run the relevant commands you want.

ayal may remember better
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

Re: [Users] oVirt support for backup/restore

[Gianluca Cecchi]

On Fri, Apr 19, 2013 at 9:58 AM, Itamar Heim wrote:

>
> qemu-guest-agent isn't ovirt/rhev-guest-agent.
> now that qemu started their own guest agent, ovirt/rhev-guest-agent isn't
> used for things covered by the qemu-guest-agent.

Ah, ok.
SO after reading
http://wiki.libvirt.org/page/Qemu_guest_agent
some questions

can we use ootb qemu-guest-agent with ovirt 3.2.1 if we have for
example a CentOS 6 guest (with qemu-guest-agent-0.12.1.2-2.355)?
Does oVirt create a virtio-serial port to communicate with libvit and
does it use libvirt with any options to quiesce  fs on guest?

Can one use as an alternative the command fsfreeze in CentOS 6.4 guest
(even if in tech preview) as in :
https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Technical_Notes/storage.html

Gianluca
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

Re: [Users] oVirt support for backup/restore

[Itamar Heim]

On 04/19/2013 10:33 AM, Gianluca Cecchi wrote:

On Mon, Mar 4, 2013 at 2:02 PM, Itamar Heim  wrote:


in general, you are correct - you don't care about live snapshot with
memory, since you probably mostly care about backing up the disks.
you may care, depending on the type of guest, on having a qemu-guest-agent
installed, which would help with syncing the writes to the disks before the
live snapshot is taken.

something to test though is if a daily snapshot does not degrade the
performance of the running VM, due to more COW layers (until the backup api
and live merge are in place).


hello, coming back to this topic.

when you say
"
you may care, depending on the type of guest, on having a
qemu-guest-agent installed, which would help with syncing the writes
to the disks
"

do you refer to something in particular already implemented as a
command or something similar?
I have a CentOS 6 guest with rhev-guest-agent taken by dreyu repoan
dwould like to test what available in case.

Thanks,
Gianluca



qemu-guest-agent isn't ovirt/rhev-guest-agent.
now that qemu started their own guest agent, ovirt/rhev-guest-agent 
isn't used for things covered by the qemu-guest-agent.

___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

Re: [Users] oVirt support for backup/restore

[Gianluca Cecchi]

On Mon, Mar 4, 2013 at 2:02 PM, Itamar Heim  wrote:

> in general, you are correct - you don't care about live snapshot with
> memory, since you probably mostly care about backing up the disks.
> you may care, depending on the type of guest, on having a qemu-guest-agent
> installed, which would help with syncing the writes to the disks before the
> live snapshot is taken.
>
> something to test though is if a daily snapshot does not degrade the
> performance of the running VM, due to more COW layers (until the backup api
> and live merge are in place).

hello, coming back to this topic.

when you say
"
you may care, depending on the type of guest, on having a
qemu-guest-agent installed, which would help with syncing the writes
to the disks
"

do you refer to something in particular already implemented as a
command or something similar?
I have a CentOS 6 guest with rhev-guest-agent taken by dreyu repoan
dwould like to test what available in case.

Thanks,
Gianluca
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

Re: [Users] oVirt support for backup/restore

[Itamar Heim]

On 04/03/2013 14:57, Ricky Schneberger wrote:

On 2013-03-04 13:24, Jiri Belka wrote:

On Mon, 04 Mar 2013 12:52:53 +0100 Ricky Schneberger
 wrote:


Live snapshot does not save memory state, IIRC. So either
shutdown all VMs or do not think about this as solid backup
solution.



Hi, If I dont think about it as a solid solution, is it doable?
Even with a manual live snapshot I will lack this memory state,
right?

All I want if I must restore a snapshot is to get the WM up on
track in an earlier state.


The "snapshot" like in VMWare world which saves even memory is
called checkpoint in qemu-kvm world. And IIRC it is not implemented
yet.

Live snapshot is doable, no problem. The problem can be your
design. As you know a lot of apps do not write to filesystem
immediately, so snapshot backup is useless. So either
shutdown/think twice or forget it.

But others can have different view... Backup is thing you _must_
trust, if you design is broken, the consequences are terrific! If
your goal is to have fast disaster recovery, then why not to have
backup machine or some clustered solution?

jbelka



Thanks for your answer.

We have both Netvault and Acronis on the most of the VMs, but then we
have other VMs in the cluster that we want a daily scheduled snapshot
implementation on, but we dont want to setup a complete backup
solution on this VMs. It's testmachines, different virtual desktops,
OCR-readers and so on. We have no needs of snapshots like in VMWare
world for them, nor even a complete backup solution. There I think
Ovirts snapshot handling should be perfect.



in general, you are correct - you don't care about live snapshot with 
memory, since you probably mostly care about backing up the disks.
you may care, depending on the type of guest, on having a 
qemu-guest-agent installed, which would help with syncing the writes to 
the disks before the live snapshot is taken.


something to test though is if a daily snapshot does not degrade the 
performance of the running VM, due to more COW layers (until the backup 
api and live merge are in place).

___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

Re: [Users] oVirt support for backup/restore

[Ricky Schneberger]

On 2013-03-04 13:24, Jiri Belka wrote:
> On Mon, 04 Mar 2013 12:52:53 +0100 Ricky Schneberger
>  wrote:
> 
>>> Live snapshot does not save memory state, IIRC. So either
>>> shutdown all VMs or do not think about this as solid backup
>>> solution.
>>> 
>> 
>> Hi, If I dont think about it as a solid solution, is it doable? 
>> Even with a manual live snapshot I will lack this memory state,
>> right?
>> 
>> All I want if I must restore a snapshot is to get the WM up on
>> track in an earlier state.
> 
> The "snapshot" like in VMWare world which saves even memory is
> called checkpoint in qemu-kvm world. And IIRC it is not implemented
> yet.
> 
> Live snapshot is doable, no problem. The problem can be your
> design. As you know a lot of apps do not write to filesystem
> immediately, so snapshot backup is useless. So either
> shutdown/think twice or forget it.
> 
> But others can have different view... Backup is thing you _must_
> trust, if you design is broken, the consequences are terrific! If
> your goal is to have fast disaster recovery, then why not to have
> backup machine or some clustered solution?
> 
> jbelka
> 

Thanks for your answer.

We have both Netvault and Acronis on the most of the VMs, but then we
have other VMs in the cluster that we want a daily scheduled snapshot
implementation on, but we dont want to setup a complete backup
solution on this VMs. It's testmachines, different virtual desktops,
OCR-readers and so on. We have no needs of snapshots like in VMWare
world for them, nor even a complete backup solution. There I think
Ovirts snapshot handling should be perfect.

//Ricky


0xB88C0B63.asc
Description: application/pgp-keys
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

Re: [Users] oVirt support for backup/restore

[Jiri Belka]

On Mon, 04 Mar 2013 12:52:53 +0100
Ricky Schneberger  wrote:

> > Live snapshot does not save memory state, IIRC. So either shutdown all
> > VMs or do not think about this as solid backup solution.
> > 
> 
> Hi, If I dont think about it as a solid solution, is it doable?
> Even with a manual live snapshot I will lack this memory state, right?
> 
> All I want if I must restore a snapshot is to get the WM up on track in
> an earlier state.

The "snapshot" like in VMWare world which saves even memory is called
checkpoint in qemu-kvm world. And IIRC it is not implemented yet.

Live snapshot is doable, no problem. The problem can be your design. As
you know a lot of apps do not write to filesystem immediately, so
snapshot backup is useless. So either shutdown/think twice or forget it.

But others can have different view... Backup is thing you _must_ trust,
if you design is broken, the consequences are terrific! If your goal is
to have fast disaster recovery, then why not to have backup machine or
some clustered solution?

jbelka
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

Re: [Users] oVirt support for backup/restore

[Ricky Schneberger]

On 2013-03-04 12:31, Jiri Belka wrote:
> On Mon, 04 Mar 2013 12:10:54 +0100
> Ricky Schneberger  wrote:
> 
>> Hi,
>>
>> How can I do if I want to schedule a daily live-snapshot of a VM for
>> backup purpose?
>>
>> I have backup software inside my VMs (Netvault), but in some cases I
>> just want to do daily snapshots and use them as backups.
>>
>>
> 
> Live snapshot does not save memory state, IIRC. So either shutdown all
> VMs or do not think about this as solid backup solution.
> 

Hi, If I dont think about it as a solid solution, is it doable?
Even with a manual live snapshot I will lack this memory state, right?

All I want if I must restore a snapshot is to get the WM up on track in
an earlier state.

regards //Ricky


0xB88C0B63.asc
Description: application/pgp-keys
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

Re: [Users] oVirt support for backup/restore

[Jiri Belka]

On Mon, 04 Mar 2013 12:10:54 +0100
Ricky Schneberger  wrote:

> Hi,
> 
> How can I do if I want to schedule a daily live-snapshot of a VM for
> backup purpose?
> 
> I have backup software inside my VMs (Netvault), but in some cases I
> just want to do daily snapshots and use them as backups.
> 
> 

Live snapshot does not save memory state, IIRC. So either shutdown all
VMs or do not think about this as solid backup solution.
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

[Users] oVirt support for backup/restore

[Ricky Schneberger]

Hi,

How can I do if I want to schedule a daily live-snapshot of a VM for
backup purpose?

I have backup software inside my VMs (Netvault), but in some cases I
just want to do daily snapshots and use them as backups.


-- 
Ricky Schneberger



0xB88C0B63.asc
Description: application/pgp-keys
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

[Users] oVirt support for backup/restore

[Deepak C Shetty]

Hi All,
I was advised on #ovirt IRC to send a mail to know more on the new 
changes happening in the oVirt backup / restore area. Below is the IRC 
chatlog for reference.


/ Hello, i was looking for info on how VM backups work in 
ovirt env.  From the docs, it seems one has to export the VM to the 
export domain and then backup from there ?
 Exporting VM to export domain does a full copy of the vm 
image, is it possible to do backup from a snapshot if i had one, in 
ovirt setup ?


 deepakcs: hey, we do not have direct backup from snapshot

 lpeer, but that means.. anytime we need to backup, we are 
creating a full copy which is taking much more space.. having backups 
from snapshot is more preferred, space and timewise, ?


 deepakcs: yes you are right we are working on a backup solution
 deepakcs: abaron ping

 deepakcs: abaron can give you more information on the backup API 
we are working on


 lpeer, okay, is there any wiki page on this on ovirt wiki ?

 deepakcs: I can't find one but it is better to write a question 
to the users mailling list

 lpeer, thanks
/

I was wondering if anyone has more info on what being proposed and/or 
changed in the backup/restore area, what to look forward to ?


thanx,
deepak

___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users