Is there a reason why you could not just use a Cinder Volume for your data, in this case?
While at a first glance, it feels rather wrong, and un-cloudy, I do see something useful about refreshing the base disk, and leaving the data disks alone. Prehaps it's something that could be described in the block device mapping, where you have a "local volume" that you choose to be non-ephemeral, except for server terminate, or something like that? John On 28 October 2013 02:00, Robert Collins <robe...@robertcollins.net> wrote: > For context, in TripleO we have precious state to preserve when we > push updates out to a cluster: nova instance volumes (obviously), > swift data stores, mysql db's etc. We have a long term plan to have a > volume model and interface that with Cinder, but thats an Ironic > planed feature, and somewhat down the track : in the short term we'd > like to use the ephemeral volume for such storage: it seems like 'nova > rebuild' could easily be extended to preserve the ephemeral block > device. > > From a nova bm perspective, all that needs to happen is for us to > /not/ format the volume - simples - and we can do that in the current > rebuild code path where destroy + spawn is called, as long as we end > up on the same host. > > However, we'd like to support this for libvirt too, because that lets > us test workflows in virt rather than on purely baremetal (or emulated > baremetal). For that, it looks to me like we need to push rebuild down > a layer to the virt driver : so rather than destroy(); spawn(); have a > rebuild() method that takes the same data spawn would, and will be > able to preserve data as needed. > > Seeking thoughts on this - both the use of ephemeral in this way, and > sketched out code change - are sought! > > Thanks, > Rob > > -- > Robert Collins <rbtcoll...@hp.com> > Distinguished Technologist > HP Converged Cloud > > _______________________________________________ > OpenStack-dev mailing list > OpenStackfirstname.lastname@example.org > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev _______________________________________________ OpenStack-dev mailing list OpenStackemail@example.com http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev