Open Stack

On 01/25/2017 03:19 AM, Eugen Block wrote:
> All these instances are in our ceph cluster.
>
> The instance path is defined in nova.conf:
>
> # Where instances are stored on disk (string value)
> instances_path = $state_path/instances
>
> If one compute node fails but it's able to initiate a migration, the
> same instance directory is created on the new host and the disks are
> copied to its new compute node.

Why would ephemeral instance disks be copied if the backing store is a 
shared system like Ceph. There would be no need to copy a disk image 
since the destination host's /var/lib/nova/instances directory is 
exactly the same as the source's, right?

Best,
-jay