命令查看某个特定pool分布在哪些osd上
思路：get pool crush_rule --> crush rule dump ---> ceph osd tree
[root@localhost store]# rados lspools
zone1.rgw.buckets.data
.rgw.root
zone1.rgw.buckets.index
[root@localhost store]# ceph osd pool get zone1.rgw.buckets.index crush_rule
crush_rule: replicated_rule （replicated_rule只是个名字，这个名字可以叫别的，具体副本还是ec，几副本，要看pool的detail）
[root@localhost store]# ceph osd crush rule dump replicated_rule
{
"rule_id": 0,
"rule_name": "replicated_rule",
"ruleset": 0,
"type": 1,
"min_size": 1,
"max_size": 10,
"steps": [
{
"op": "take",
"item": -1,
"item_name": "default" （得到crush rule dump）
},
[root@localhost store]# ceph osd tree | grep -v osd
ID CLASS WEIGHT TYPE NAME STATUS REWEIGHT PRI-AFF
-76 540.00000 root hdd-root-1
-9 30.00000 host DN-001
-11 30.00000 host DN-002
-10 30.00000 host DN-003
-1 18.00000 root default （得到目的osd分布）
-7 6.00000 host MN-001
-2 6.00000 host MN-002
-6 6.00000 host MN-003
