[Engine-devel] SharedRawDisk feature detail

[Itamar Heim]

On 02/05/2012 02:14 PM, Maor wrote:
...

>> 3. "The synchronization/clustering of shared raw disk between VMs will
>> be managed in the file system. "
>>
>> either i don't understand what this mean, or it could be read with a
>> misleading meaning.
> Maybe the following rephrase will be more accurate: "The
> synchronization/clustering of shared raw disk between VMs should be
> based on external independent application which will be synchronized
> with the guest application."
"The synchronization/clustering of shared raw disk between VMs is the 
responsibility of the guests. Unaware guests will lead to corruption of 
the shared disk."

>>
>> 4. VM Pools
>> VM Pools are always based (at least today) on templates, and templates
>> have no shared disks.
>> I'd just block attaching a shared disk to a VM which is part of a pool
>> (unless there is a very interesting use case meriting this)
> If there is no reason to attach shared disk to a VM from pool, maybe its
> also not that relevant to attach shared disk to stateless VM.
> Miki?

I think pools and stateless are different. I can envision a use case 
where stateless guests would use a shared disk (say, in read only for 
same data).


>>
>> 6. future work - Permissions should be added for disk entity
>> so who can add a shared disk?
> Data Center Administrator or System Administrator will be initialized
> with permissions for creating shared raw disk, or changing shared disk
> to be unshared.
> Regarding attach/detach disks to/from VM, I was thinking that for phase
> one we will count on the user VM permissions. If user will have
> permissions to create new disks on the VM, he will also have permissions
> to attach new shared raw disk to it.

this means they can attach shared disks from other VMs they have no 
permission on...
as i said earlier - need to think about this one some more.