Hi, on a healthy cluster, every osd creation made orphans osd. # ceph osd tree ID CLASS WEIGHT TYPE NAME STATUS REWEIGHT PRI-AFF -1 26.38051 root default -7 3.63869 host A 1 hdd 3.63869 osd.1 up 1.00000 1.00000 -11 1.81940 host F 2 hdd 1.81940 osd.2 up 1.00000 1.00000 -5 7.27737 host J 3 hdd 3.63869 osd.3 up 1.00000 1.00000 5 hdd 3.63869 osd.5 up 1.00000 1.00000 -3 7.27737 host K 0 hdd 3.63869 osd.0 up 1.00000 1.00000 8 hdd 3.63869 osd.8 up 1.00000 1.00000 -9 6.36768 host S 6 hdd 3.63869 osd.6 up 1.00000 1.00000 7 hdd 2.72899 osd.7 up 1.00000 1.00000 4 0 osd.4 down 0 1.00000 9 0 osd.9 down 0 1.00000 neither 4 nor 9 osd appear in the crushmap (decompiled) Destroying and recreating osd recreate orphan osd. Any hint ?Thanks for all Best regardsPhilippe