On Wed, 2020-10-14 at 18:38 +0530, Deepa KR wrote:
Hi All
Good Day
From documentation we are able to understand that we can configure multiple backends for cinder (Ceph ,External Storage device or NFS etc) Is there any way we can choose the backend while instance launching .Say
instance1 backend should be from an external storage device like EMCÂ and instance2 to launch and have backend volume from ceph
kind of you can use volume types to do this indrectly. end users shoudl generally not be aware if its ceph or an emc san you less you name the volumens tyeps "cpeh" and "emc" but that is a operator choice. you can map the volume type to specific backend using there config file.
.Can this be achieved using cinder availability zone implementation or any other way?
I have gone through below link (*section Configure Block Storage scheduler multi back end)*
https://docs.openstack.org/cinder/latest/admin/blockstorage-multi-backend.ht...
well that basically covers what you have to do
your cinder config for lvm emc and ceph might look like this
[DEFAULT] enabled_backends=lvm,emc,ceph
[lvm] volume_group = cinder-volume-1 volume_driver = cinder.volume.drivers.lvm.LVMVolumeDriver
[emc] use_multipath_for_image_xfer = true volume_driver = cinder.volume.drivers.emc.emc_smis_fc.EMCSMISFCDriver volume_backend_name = emcfc
[ceph] volume_driver = cinder.volume.drivers.rbd.RBDDriver volume_backend_name = ceph rbd_pool = volumes rbd_ceph_conf = /etc/ceph/ceph.conf rbd_flatten_volume_from_snapshot = false rbd_max_clone_depth = 5 rbd_store_chunk_size = 4 rados_connect_timeout = -1
or you might have 3 diffent config one for each
you then create 3 different volume types and assocatie each with a backend
openstack --os-username admin --os-tenant-name admin volume type create lvm openstack --os-username admin --os-tenant-name admin volume type create emc openstack --os-username admin --os-tenant-name admin volume type create ceph
openstack --os-username admin --os-tenant-name admin volume type set lvm --property volume_backend_name=lvm openstack --os-username admin --os-tenant-name admin volume type set emc --property volume_backend_name=emc openstack --os-username admin --os-tenant-name admin volume type set ceph --property volume_backend_name=ceph
then you can create volumes with those types
openstack volume create --size 1 --type lvm my_lvm_volume openstack volume create --size 1 --type ceph my_ceph_volume
and boot a server with them.
openstack server create --volume my_lvm_volume --volume my_ceph_volume ...
if you have cross az attach disabel in nova and you want all type/backend to be accesable in all AZ you need to deploy a instance of the cinder volume driver for each of the tyeps in each az.
i dont know if that answers your question or not but volume types are the way to requst a specific backend at the api level.
Suggestions please ..
Regards, Deepa K R