Hi guys, I have stumbled over an error that I cannot solve after more than 2 days trying. Now I turn to you in hope to get some help! :) First of all, I am totally new to Ceph and this is just a test setup for now. I have followed the instructions on the ceph.com homepage as far as I understand. I am about to set up a Ceph storage cluster on three different nodes (running Ubuntu server 20.04). I am using Ceph Octopus. On these 3 nodes I have installed 3 monitors, 3 managers and 12 OSDs (I do know that OSDs and Monitors on the same machines are not recommended but for this test setup I do it anyway). So far is everything working well for me. However, when I try to create an RBD pool it fails with some strange (at least strange for me) error message: 2020-10-08T07:48:36.601+0000 7f8b9b7fe700 -1 librbd::image::GetMetadataRequest: 0x564279b9d670 handle_metadata_list: failed to retrieve image metadata: (1) Operation not permitted 2020-10-08T07:48:36.601+0000 7f8bb6af8380 -1 librbd::PoolMetadata: list: failed listing metadata: (1) Operation not permitted 2020-10-08T07:48:36.601+0000 7f8bb6af8380 -1 librbd::Config: apply_pool_overrides: failed to read pool config overrides: (1) Operation not permitted 2020-10-08T07:48:36.601+0000 7f8b9b7fe700 -1 librbd::image::ValidatePoolRequest: handle_read_rbd_info: failed to read RBD info: (1) Operation not permitted rbd: pool already registered to a different application. I run the commands as the Linux root user and as the Ceph user client.admin (I have turned off apparmor and other hardening things as well). The chep user client.admin has the following setup in its keyring: [client.admin] key = ..... caps mds = "allow *" caps mgr = "allow *" caps mon = "allow *" For more information regarding permissions in the system see the attached file permissions.txt that contains the output of the ceph auth list command. I have also attached a file (report.txt) containing the output from the ceph report command. (NOTE: I have removed some information from the files, i.e. keys, fsid, fingerprints, uuid, and replaced them with "..." instead) Can anyone please help me understand why I get this error and what I need to do in order to solve it? Thanks in advanced! Best regards, Fredrik