Sorry, I just got on this list and am asking a number of questions… ☹ It was suggested in one of my other threads to create and apply a spec file that would have cephadm put the DB for rotational drives onto SSD when it creates the OSD on those drives. I came up with he following spec file: --- START --- service_type: osd service_id: osd_spec_hdd placement: host_pattern: '*' data_devices: rotational: 1 db_devices: rotational: 0 model: 'Samsung SSD 990 PRO 1TB' limit: 1 --- service_type: osd service_id: osd_spec_ssd placement: host_pattern: '*' data_devices: model: 'KINGSTON SEDC1500M1920G' --- END --- But when I run ‘ceph orch apply osd -i ./osd_spec.yml --dry-run’, I get the following output: --- START --- WARNING! Dry-Runs are snapshots of a certain point in time and are bound to the current inventory setup. If any of these conditions change, the preview will be invalid. Please make sure to have a minimal timeframe between planning and applying the specs. #################### SERVICESPEC PREVIEWS #################### +---------+------+--------+-------------+ |SERVICE |NAME |ADD_TO |REMOVE_FROM | +---------+------+--------+-------------+ +---------+------+--------+-------------+ ################ OSDSPEC PREVIEWS ################ +---------+------+------+------+----+-----+ |SERVICE |NAME |HOST |DATA |DB |WAL | +---------+------+------+------+----+-----+ +---------+------+------+------+----+-----+ --- END --- Which seems to indicate that nothing would be applied, but I am not sure if that is because my spec file is wrong or if it is because my rotational drives already have OSDs (and I have migrated their DB/WAL to the SSDs)?