[one-users] Best way to migrate datastores 0 & 1 to new storage area

[Alexandre Bezroutchko]

On 04/22/2013 03:33 PM, Gerry O'Brien wrote:
> Hi Alex,
>
>     Thanks for the interesting reply. We are running kvm/qemu so I'm
> not sure how this would work for us although we may use it in out
> Citrix infrastructure. I have a question: after the xNDB proxy is
> shutdown and restarted where does the cache get stored?
Probably "cache.img" file you specify as an argument to 'xnbd-server
--proxy ...' command.
>
>     In our OpenNebula installation, is it possible to switch system
> the datastore from 0 to some other datastore without interruption?
I'm not an OpenNebula expert by a long shot, hope other people will
correct me if I'm wrong. My guess is Opennebula will not like the idea
of you messing with datastore containing images used by live VMs. On
another hand, even if you shut down Opennebula completely, it will not
affect already running VMs. So you will be free to migrate your VMs
around and remount/reformat filesystems. Just put everything back in
place before you restart OpenNebula again. Might work, but it is not
something I have tried myself.

>
>         Regards,
>             Gerry
>
>
> On 19/04/2013 14:50, Alexandre Bezroutchko wrote:
>> On 04/18/2013 06:42 PM, Gerry O'Brien wrote:
>>> Hi,
>>>
>>>      We would like to migrate out installation to a new storage, so
>>> that we can use ZFS instead of EXT4 for datastores 0 and 1. Are there
>>> guidelines on how best to achieve this? If we just shut-down the
>>> service it will take a long time to move existing files as they are
>>> large so the disruption will be substantial.
>> I would be interested to know a proper answer to this question too. To
>> my knowledge such an operation would be outside of what Opennebula
>> can/want to support, but you probably can achieve what you want with
>> some trickery.
>>
>> If you can afford some downtime, you can try using the following
>> approach to keep it to minimum:
>> http://www.bouncybouncy.net/ramblings/posts/xen_live_migration_without_shared_storage.
>>
>>
>> If you are looking for even shorted downtimes, there is another trick
>> described here
>> https://bitbucket.org/hirofuchi/xnbd/wiki/Home#!scenario-3-live-vm-disk-migration-with-xen.
>>
>> Note that the article's title suggests this is xen-specific, there are
>> some kvm/qemu-specific information in the article.
>>
>> What hypervisor you use?
>>
>> Best regards,
>> Alex
>>>          Regards,
>>>              Gerry
>>>
>> _______________________________________________
>> Users mailing list
>> Users at lists.opennebula.org
>> http://lists.opennebula.org/listinfo.cgi/users-opennebula.org
>
>