On 30/04/18 12:51, Tony Brian Albers wrote:
On 30/04/18 11:43, Eduardo Mayoral wrote:
> Hi,
>
> I would like to set up a new oVirt deployment with hosts that have
> the VMs running on local attached storage. I understand this has the
> requirement of having each host in its own cluster (and own datacenter,
> it seems, I understand the need for the dedicated cluster, not so much
> for the dedicated datacenter).
>
> At the same time, I would like to have some shared storage domains
> so I can use it to export VMs or migrate them around hosts (probably in
> three stages, first migrate VM storage from local to the shared storage
> domain, second migrate the host (probably not possible to do a "hot"
> migration, but at least "cold"), third migrate the VM storage from the
> shared storage domain to the local storage domain of the new host).
>
> So I thought maybe I can deploy a datacenter in shared storage mode,
> with one cluster per host. Use one or two shared storage domains for
> master and as an stage area for planned VM migrations as explained
> before, and then configure several storage domains, one per host, as
> posix FS . I would then deploy the VMs on the local posix FS storage
> domains and set affinity rules for the VMs to their hosts as needed.
>
> Would this work? Is there a better way of achieving local storage
> and retaining the ability to share storage among hosts and migrate VMs?
>
>
Have you thought about using glusterfs? If hosts are physically close,
that would probably be the best solution.
Actually, yes, I also had glusterfs in mind. However one of the main
reasons to use local storage is performance, and I am concerned about
the write latencies of gluster (If using gluster, I would handle things
so the VM runs on one of the gluster nodes hosting the VM data, so I
assume the read latency will be close to the one I would get with local
storage, but the gluster replica(s) will be on other hosts, so write
latency may be significantly worse).
Thanks a lot for the suggestion, it is a good one, however, the original
question stands: Would this work? Is there a better way of achieving
local storage and retaining the ability to share storage among hosts and
migrate VMs?
Best regards,
--
Eduardo Mayoral.