Enable the ceph-volume tool¶

This section describes how to enable the ceph-volume command-line tool that enables you to deploy and inspect Ceph OSDs using the Logical Volume Management (LVM) functionality for provisioning block devices. The main difference between ceph-disk and ceph-volume is that ceph-volume does not automatically partition disks used for block.db. However, partitioning is performed within the procedure below.

To enable the ceph-volume tool:

1. Open your Git project repository with the Reclass model on the cluster level.

2. Open ceph/osd.yml for editing.

3. Set the lvm_enabled parameter to True:

   parameters:
     ceph:
       osd:
         lvm_enabled: True
   

4. For each Ceph OSD, add the definition of a bare block.db partition and define its number in db_partition. For example:

   parameters:
     ceph:
       osd:
         backend:
           bluestore:
             disks:
               - dev: /dev/vdc
                 block_db: /dev/vdd
                 db_partition: 1
     linux:
       storage:
         disk:
           /dev/vdd:
             type: gpt
             partitions:
               - size: 10000
   

   Note

   Due to a custom disk layout, these definitions may already exist and be configured differently. In this case, verify that the db_partition number is defined.

5. Apply the changes:

   salt -C 'I@ceph:osd' saltutil.refresh_pillar
   

   Once done, all new Ceph OSDs will be deployed using ceph-volume instead of ceph-disk. The existing Ceph OSDs will cause errors during common operations and must be redeployed or defined as legacy_disks as described below.

6. Select from the following options:

   • Redeploy Ceph OSD nodes or daemons:

     Warning

     Before redeploying a node, verify that all pools have at least three copies. Redeploy only one node at a time. Redeploying multiple nodes may cause irreversible data loss.

     • Prior to MCP 2019.2.13, redeploy the Ceph OSD nodes:
       1. Remove the OSD nodes as described in Remove a Ceph OSD node.
       2. Add new OSD nodes as described in Add a Ceph OSD node.
     • Starting from MCP 2019.2.13, redeploy the Ceph OSD daemons:
       1. Remove the Ceph OSD daemons as described in Remove a Ceph OSD daemon.
       2. Add new Ceph OSD daemons as described in Add a Ceph OSD daemon.

   • Define existing Ceph OSDs as legacy_disks by specifying the legacy_disks pillar for each Ceph OSD in ceph/osd.yml. For example:

     parameters:
       ceph:
         osd:
           legacy_disks:
             0:
               class: hdd
               weight: 0.048691
               dev: /dev/vdc
     

     Note

     Use the legacy_disks option only as a temporary solution for common management of the cluster during the transition period.