Hi to all and thanks for sharing your experience on ceph ! We have an easy setup with 9 osd all hdd and 3 nodes, 3 osd for each node. We started the cluster to test how it works with hdd with default and easy bootstrap . Then we decide to add ssd and create a pool to use only ssd. In order to have pools on hdd and pools on ssd only we edited the crushmap to add class hdd We do not enter anything about ssd till now, nor disk or rules only add the class map to the default rule. So i show you the rules before introducing class hdd # rules rule replicated_rule { id 0 type replicated min_size 1 max_size 10 step take default step chooseleaf firstn 0 type host step emit } rule erasure-code { id 1 type erasure min_size 3 max_size 4 step set_chooseleaf_tries 5 step set_choose_tries 100 step take default step chooseleaf indep 0 type host step emit } rule erasure2_1 { id 2 type erasure min_size 3 max_size 3 step set_chooseleaf_tries 5 step set_choose_tries 100 step take default step chooseleaf indep 0 type host step emit } rule erasure-pool.meta { id 3 type erasure min_size 3 max_size 3 step set_chooseleaf_tries 5 step set_choose_tries 100 step take default step chooseleaf indep 0 type host step emit } rule erasure-pool.data { id 4 type erasure min_size 3 max_size 3 step set_chooseleaf_tries 5 step set_choose_tries 100 step take default step chooseleaf indep 0 type host step emit } And here is the after # rules rule replicated_rule { id 0 type replicated min_size 1 max_size 10 step take default class hdd step chooseleaf firstn 0 type host step emit } rule erasure-code { id 1 type erasure min_size 3 max_size 4 step set_chooseleaf_tries 5 step set_choose_tries 100 step take default class hdd step chooseleaf indep 0 type host step emit } rule erasure2_1 { id 2 type erasure min_size 3 max_size 3 step set_chooseleaf_tries 5 step set_choose_tries 100 step take default class hdd step chooseleaf indep 0 type host step emit } rule erasure-pool.meta { id 3 type erasure min_size 3 max_size 3 step set_chooseleaf_tries 5 step set_choose_tries 100 step take default class hdd step chooseleaf indep 0 type host step emit } rule erasure-pool.data { id 4 type erasure min_size 3 max_size 3 step set_chooseleaf_tries 5 step set_choose_tries 100 step take default class hdd step chooseleaf indep 0 type host step emit } Just doing this triggered the misplaced of all pgs bind to EC pool. Is that correct ? and why ? Best regards Alessandro Bolgia _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx