Notice

This document is for a development version of Ceph.

systemdΒΆ

Upon startup, it will identify the logical volume using LVM tags, finding a matching ID and later ensuring it is the right one with the OSD uuid.

After identifying the correct volume it will then proceed to mount it by using the OSD destination conventions, that is:

/var/lib/ceph/osd/<cluster name>-<osd id>

For our example OSD with an id of 0, that means the identified device will be mounted at:

/var/lib/ceph/osd/ceph-0

Once that process is complete, a call will be made to start the OSD:

systemctl start ceph-osd@0

The systemd portion of this process is handled by the ceph-volume lvm trigger sub-command, which is only in charge of parsing metadata coming from systemd and startup, and then dispatching to ceph-volume lvm activate which would proceed with activation.