Using batch mode

The batch subcommand automates the creation of multiple OSDs when single devices are provided.

The ceph-volume command decides the best method to use to create the OSDs, based on drive type. Ceph OSD optimization depends on the available devices:

  • If all devices are traditional hard drives, batch creates one OSD per device.

  • If all devices are solid state drives, batch creates two OSDs per device.

  • If there is a mix of traditional hard drives and solid state drives, batch uses the traditional hard drives for data, and creates the largest possible journal (block.db) on the solid state drive.

Note: The batch subcommand does not support the creation of a separate logical volume for the write-ahead-log (block.wal) device.

Prerequisites

  • A running IBM Storage Ceph cluster.
  • Root-level access to the Ceph OSD nodes.

Procedure

  1. To create OSDs on several drives: 
    ceph-volume lvm batch --bluestore PATH_TO_DEVICE [PATH_TO_DEVICE]

    Example 

    [ceph: root@host01 /]# ceph-volume lvm batch --bluestore /dev/sda /dev/sdb /dev/nvme0n1