Hi I tried to do offline read optimization[1] this morning but I am now unable to map the RBDs in the pool. I did this prior to running the pg-upmap-primary commands suggested by the optimizer, as suggested by the latest documentation[2]: " ceph osd set-require-min-compat-client reef " The command didn't complain and the documentation stated it should failed if any pre-reef clients were connected so I thought all was well and rad the pg_upmap_primary commands. Can I simply remove the applied pg_upmap_primary settings somehow to my RBDs back while investigating? Mvh. Torkil [1] https://docs.ceph.com/en/reef/rados/operations/read-balancer/ [2] https://docs.ceph.com/en/latest/rados/operations/read-balancer/ -- Torkil Svensgaard Sysadmin MR-Forskningssektionen, afs. 714 DRCMR, Danish Research Centre for Magnetic Resonance Hvidovre Hospital Kettegård Allé 30 DK-2650 Hvidovre Denmark Tel: +45 386 22828 E-mail: torkil@drcmr.dk