如何调整pool的crush rule

前期准备一、确定pool使用哪个crush rule（关注rule id）

[root@node12 ~]# ceph osd pool ls detail
pool 2 'vol-ssd' replicated size 3 min_size 2 crush_rule 8 object_hash rjenkins pg_num 2048 pgp_num 2048 autoscale_mode warn last_change 310506 lfor 0/0/52959 flags hashpspool,selfmanaged_snaps stripe_width 0 pg_num_min 2048 application cephfs,rbd,rgw
pool 4 'vol-hdd' replicated size 3 min_size 2 crush_rule 6 object_hash rjenkins pg_num 2048 pgp_num 2048 autoscale_mode warn last_change 293441 lfor 0/0/97498 flags hashpspool,selfmanaged_snaps stripe_width 0 pg_num_min 2048 application rbd
pool 6 'vol-sas' replicated size 3 min_size 2 crush_rule 7 object_hash rjenkins pg_num 512 pgp_num 512 autoscale_mode warn last_change 299036 flags hashpspool,selfmanaged_snaps stripe_width 0 application rbd

方式一：导入更新方式(若需对已存在的rule修改故障域，请使用该方式)

#1、查看当前osd的类型列表
root@pve-ceph01:~# ceph osd crush class ls      #查看当前osd的类型列表
[
    "hdd",
    "ssd"
]

#2、导出crushmap，export osd crushmap
    ceph osd getcrushmap -o map.bin    #导出成bin格式
    crushtool -d map.bin -o map.txt    #转换成文本格式

#3、编辑 map.txt 文件，添加如下两个规则
rule rule-ssd {
    id 1
    type replicated
    min_size 1
    max_size 10
    step take default class ssd
    step chooseleaf firstn 0 type host
    step emit
}
rule rule-hdd {
    id 2
    type replicated
    min_size 1
    max_size 10
    step take default class hdd
    step chooseleaf firstn 0 type host
    step emit
}

#4、导入crushmap，import osd crushmap
    crushtool -c map.txt -o map_new.bin    #将文本格式处理为bin格式
    ceph osd setcrushmap -i map_new.bin    #导入bin格式

#5、创建名为volumes-ssd的pool，并应用rule-ssd规则
    ceph osd pool create volumes-ssd 32 32 replicated rule-ssd

    #或者修改名称为volumes-hdd池的crush rule 为rule-hdd
    ceph osd pool set volumes-hdd crush_rule rule-hdd 

方拾二：命令更新方式（推荐）

#1、创建pool的rule，并设置故障域
    ceph osd crush rule create-replicated rule-hdd default host hdd     #为class 类型为 hdd的硬盘创建一个 名为 rule-hdd的 rule策略，故障域为host(创建HDD rule)
    ceph osd crush rule create-replicated rule-ssd default host ssd     #为class 类型为 ssd的硬盘创建一个 名为 rule-ssd的 rule策略，故障域为host(创建SSD rule)

#2、为pool 应用crush rule规则（若pool已应用了rule，就是修改rule）
    #ceph osd pool set <poolname> crush_rule <rule-name>
    ceph osd pool set volumes-ssd crush_rule rule-ssd                   #为名为volumes-ssd的pool应用 名为rule-ssd的crush规则
    ceph osd pool create volumes-ssd 32 32 replicated rule-ssd          #或者是在创建pool的时候指定crush rule 创建名为volumes-ssd的pool，并应用rule-ssd规则

附、如何更改osd的class 类型

更改osd的 class 类型
    ceph osd crush rm-device-class osd.9        #更改class前，先必须删除原本的class
    ceph osd crush set-device-class ssd osd.9   #class类型可以是hdd,ssd,sas,nvme
    #ceph osd crush set-device-class ssd 9      #效果同上
    #ceph osd crush set-device-class ssd osd.0 osd.1 osd.4 osd.5        #一次性设置多个osd
    #ceph osd crush set-device-class ssd 0 1 4 5

查看crush rule（名为 rule-ssd）的详细信息
    ceph osd crush rule dump rule-ssd