Ceph new

ceph osd status
ceph osd purge osd.3 --yes-i-really-mean-it

Purge vs Destroy

In Ceph, both ceph osd destroy and ceph osd purge commands are used to remove OSDs (Object Storage Daemons) from the cluster, but they serve different purposes and have different effects:

ceph osd destroy:

Purpose: The ceph osd destroy command is used to remove an OSD from the cluster, including its data and configuration. Effects: When you run ceph osd destroy, Ceph marks the OSD as destroyed and removes its data and configuration from the cluster. However, the command does not remove the OSD completely from the cluster configuration. The OSD is still listed in the cluster map, but it is marked as destroyed and no longer actively participating in the cluster. Usage: Typically, ceph osd destroy is used when decommissioning OSDs or replacing disks, but you want to keep a record of the OSD's existence in the cluster map. ceph osd purge:

Purpose: The ceph osd purge command is used to completely remove an OSD from the cluster, including its data, configuration, and authentication keys. Effects: When you run ceph osd purge, Ceph permanently removes all traces of the OSD from the cluster. This includes removing its data, configuration, authentication keys, and any other associated information. The OSD is completely eliminated from the cluster configuration. Usage: ceph osd purge is used when you want to permanently remove an OSD from the cluster, such as when decommissioning a node or disk and ensuring that no traces of the OSD remain in the cluster configuration. In summary, ceph osd destroy marks an OSD as destroyed but keeps its record in the cluster map, while ceph osd purge completely removes the OSD from the cluster, ensuring that no traces of the OSD remain. Use ceph osd purge with caution, as it permanently deletes data and configuration information from the cluster. Always ensure that you have backups and a rollback plan in place before using ceph osd purge.