Hi Alex,
See my last respond, I add a comment inline there.
See my comments inline

Regards,
Maor.

On 01/17/2013 10:04 PM, Alex Leonhardt wrote:
> Hiya,
>
> Yes i can choose the storage domain, but I cannot force the host that is
> to be used for creating it. Even with 1Gbit network, creating a 80GB
> disk / 40 GB disk is still significantly longer process than actually
> required when doing a "dd" of /dev/null over the network.
>
> Is it possible to manually change who is SPM master, create the
> disks/VMs required, and change it back ?

You can maintain your SPM host, and active it back again, this will
change the SPM to be the other host which you want.

> How would that change affect the running VMs / would they try to migrate to the other HV ?

The VM migration will still be under the same cluster.

SPM is simply used to write to the storage domains, one of the reasons
we use the SPM is to avoid collisions when hosts write to the same
storage domain.

>
> Alex
>
>
> On 01/17/2013 07:39 PM, Maor Lipchuk wrote:
>> Hi Alex,
>> The storage domains are part of the Data Center, and should not be
>> related to clusters.
>> Clusters are used for migrating VMs, which are the qemu processes,
>> between hosts.
>> Disks are created on the storage domains regardless to clusters.
>>
>> The host which write the data in the storage domain to create the disk
>> is the SPM.
>> You should have only one SPM in each Data Center (You can spot which
>> host is your SPM by looking at the SPM column in the hosts tab)
>> When you create a disk you should be able to choose the storage domain
>> which you want the disk to be created on.
>>
>> Regards,
>> Maor