Hi, I want to test ceph cache tire. The test cluster has three machines, each has a ssd and a sata. I've created a crush rule ssd_ruleset to place ssdpool on ssd osd, but cannot assign pgs to ssds. root@ceph10:~# ceph osd crush rule list [ "replicated_ruleset", "ssd_ruleset"] root@ceph10:~# ceph status cluster fa5427de-b0d7-466a-b7cf-90e47eac1642 health HEALTH_OK monmap e2: 2 mons at {mona=192.168.2.10:6789/0,monb=192.168.2.11:6789/0}, election epoch 4, quorum 0,1 mona,monb osdmap e70: 6 osds: 6 up, 6 in pgmap v234: 192 pgs, 3 pools, 0 bytes data, 0 objects 251 MB used, 5853 GB / 5853 GB avail 192 active+clean root@ceph10:~# ceph osd pool create ssdpool 128 128 replicated ssd_ruleset pool 'ssdpool' created root@ceph10:~# ceph osd pool get ssdpool crush_ruleset crush_ruleset: 0 root@ceph10:~# ceph osd pool set ssdpool crush_ruleset 1 set pool 8 crush_ruleset to 1 root@ceph10:~# ceph status cluster fa5427de-b0d7-466a-b7cf-90e47eac1642 health HEALTH_OK monmap e2: 2 mons at {mona=192.168.2.10:6789/0,monb=192.168.2.11:6789/0}, election epoch 4, quorum 0,1 mona,monb osdmap e73: 6 osds: 6 up, 6 in pgmap v245: 320 pgs, 4 pools, 0 bytes data, 0 objects 4857 MB used, 5849 GB / 5853 GB avail 320 active+clean root@ceph10:/var/log/ceph# rbd list -p ssdpool ^C root@ceph10:/var/log/ceph# rbd create test --pool ssdpool --size 1024 --image-format 2 ^C The command "rbd list -p ssdpool" and "rbd create test --pool ssdpool --size 1024 --image-format 2" hung. "ceph pg dump" showed me that no pgs are on ssd osds. Why ? Why did "ceph osd pool create ssdpool 128 128 replicated ssd_ruleset" create ssdpool with crush_ruleset 0? How to set ssd_ruleset when create a pool? I used the ceph command to control crush map. ceph osd crush add-bucket ssd root ceph osd crush add-bucket ssd10 host ceph osd crush add-bucket ssd11 host ceph osd crush add-bucket ssd12 host ceph osd crush move ssd10 root=ssd ceph osd crush move ssd11 root=ssd ceph osd crush move ssd11 root=ssd ceph osd crush rule create-simple ssd_ruleset ssd root ceph osd crush add-bucket sata10 host ceph osd crush add-bucket sata11 host ceph osd crush add-bucket sata12 host ceph osd crush move sata10 root=default ceph osd crush move sata11 root=default ceph osd crush move sata12 root=default Here is my crush map: # begin crush map tunable choose_local_tries 0 tunable choose_local_fallback_tries 0 tunable choose_total_tries 50 tunable chooseleaf_descend_once 1 # devices device 0 osd.0 device 1 osd.1 device 2 osd.2 device 3 osd.3 device 4 osd.4 device 5 osd.5 # types type 0 osd type 1 host type 2 chassis type 3 rack type 4 row type 5 pdu type 6 pod type 7 room type 8 datacenter type 9 region type 10 root # buckets host sata10 { id -6 # do not change unnecessarily # weight 1.900 alg straw hash 0 # rjenkins1 item osd.3 weight 1.900 } host sata11 { id -7 # do not change unnecessarily # weight 1.900 alg straw hash 0 # rjenkins1 item osd.4 weight 1.900 } host sata12 { id -8 # do not change unnecessarily # weight 1.900 alg straw hash 0 # rjenkins1 item osd.5 weight 1.900 } root default { id -1 # do not change unnecessarily # weight 5.700 alg straw hash 0 # rjenkins1 item sata10 weight 1.900 item sata11 weight 1.900 item sata12 weight 1.900 } host ssd10 { id -2 # do not change unnecessarily # weight 1.900 alg straw hash 0 # rjenkins1 item osd.0 weight 1.900 } host ssd11 { id -4 # do not change unnecessarily # weight 1.900 alg straw hash 0 # rjenkins1 item osd.1 weight 1.900 } host ssd12 { id -5 # do not change unnecessarily # weight 1.900 alg straw hash 0 # rjenkins1 item osd.2 weight 1.900 } root ssd { id -3 # do not change unnecessarily # weight 5.700 alg straw hash 0 # rjenkins1 item ssd10 weight 1.900 item ssd11 weight 1.900 item ssd12 weight 1.900 } # rules rule replicated_ruleset { ruleset 0 type replicated min_size 1 max_size 10 step take default step chooseleaf firstn 0 type host step emit } rule ssd_ruleset { ruleset 1 type replicated min_size 1 max_size 10 step take ssd step chooseleaf firstn 0 type root step emit } # end crush map Thanks a lot! _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com