Hi, we have OSD nodes currently consisting of two 605GB SSDs and six 18TB HDDs. The hosts have room for twelve HDDs. We created a drivegroup spec that looks like this: spec: block_db_size: 100GB data_devices: rotational: true size: '18TB:' db_devices: rotational: false size: '550GB:650GB' db_slots: 6 Initially this creates 6 OSDs with their RocksDB+WAL on the SSDs, 3 each which is nice for load balancing. But when we add another HDD it gets a 17.9TB data volume and a 100GB DB volume, both on the HDD: sdm 8:192 0 18T 0 disk ├─ceph--846e1a59--aff6--4ef8--9b71--de7241531677-osd--block--026e8cef--123d--47d9--9b30--211f94edf96c 252:16 0 17.9T 0 lvm └─ceph--846e1a59--aff6--4ef8--9b71--de7241531677-osd--db--88c47d0b--f5c6--4cec--8909--c5f8036ca459 252:17 0 100G 0 lvm I would have assumed that the remaining 305GB on the SSDs would be used. How do we achieve this? Regards -- Robert Sander Heinlein Consulting GmbH Schwedter Str. 8/9b, 10119 Berlin http://www.heinlein-support.de Tel: 030 / 405051-43 Fax: 030 / 405051-19 Zwangsangaben lt. §35a GmbHG: HRB 220009 B / Amtsgericht Berlin-Charlottenburg, Geschäftsführer: Peer Heinlein -- Sitz: Berlin