Allow loop device as a LVM backend
Loop device usage is a convinient way to deploy small Ceph clusters for development, however
ceph-volume lvm create doesn't allow to use them with lsblk probing, throwing as exception
Cannot use device (/dev/loopX). The second method of device type recongnition (using python's stat module) works fine.
The patch is already submitted: https://github.com/ceph/ceph/pull/24765 and works fine in dev environment.
#2 Updated by Mariusz Strzelecki about 1 year ago
to be honest - I'm not sure. To deploy both production and testing clusters I'm using code that executes
ceph-deploy, and the manual doesn't cover this method: http://docs.ceph.com/docs/mimic/rados/deployment/ceph-deploy-osd/
I tried all possible combinations parameters passed to
ceph-deploy osd create --data <disk> <node>, but every time it fails with the message frmom
ceph-volume. But maybe I missed something?
#6 Updated by Alfredo Deza 3 months ago
ceph-volume should not concentrate on non-production criteria. Testing, and development on loop devices should be up to the implementer and not the tool to support.
In any case (and I will comment on the PR as well), it is possible to make a loop device be recognized by ceph-volume. In the functional tests, we use nvme tools to create a sparse file and attach it to a loop device and tell the kernel that it is an NVMe device. ceph-volume happily takes that and creates LVs ontop.