On 07/11/2013 12:52 PM, Piotr Szubiakowski wrote:
>> The way that oVirt manage storage domains accessed via FC is very
>> smart.
>> There is separate logical volume for each virtual disk. But I think
>> that
>> logical volume at the same time could be "touched" only by one host.
Is
>> it possible that two host access read/write the same logical volume and
>> there is no data corruption?
>
> hence a shared disk over block storage using LVM must be
> pre-allocated, so no LV changes (lv extend) would be needed.
> (also, it cannot have snapshots, since it would become qcow)
Ok, but this is the hypervisor view. For a guest OS this LV is normal
RAW block device. I wonder if someone test this feature and access
shared disk from many VM's at the same time?
I did a brief tests - 3 vms,
shared disk, cman/pacemaker + gfs2 - had no
problems using it, no data corruption. although that was only basic
tests, like create/move/delete files, no extensive usage/stress or
something like that.