Ceph Specifies OSD to create pool

https://my.oschina.net/wangzilong/blog/1549690

Mixed types of disks are allowed in the ceph cluster, for example, some disks are SSD , Part is STAT. If small high-speed disk SSDs for certain businesses require STAT for certain businesses, you can specify to create them on certain OSDs when creating a resource pool.

There are 8 basic steps:

Currently only STAT does not have SSD, but it does not affect the results of the experiment.

1 Get a crush map

[[email protected] getcrushmap]# ceph osd getcrushmap -o /opt /getcrushmap/crushmap got crush map from osdmap epoch 2482

2 Decompile crush map

[[emailprotected] getcrushmap]# crushtool -d crushmap -o decrushmap

3 Modify the crush map

Add the following two buckets after root default

root ssd {

 id -5

 alg straw

 hash 0 item osd.0 weight 0.01} root stat {id -6 ​​alg straw hash 0 item osd.1 weight 0.01} 

Add the following rules in the rules section:

rule ssd{

 ruleset 1

 type replicated min_size 1 max_size 10 step take ssd step chooseleaf firstn 0 type osd step emit} rule stat{ ruleset 2 type replicated min_size 1 max_size 10 step take stat step chooseleaf firstn 0  type osd step emit} 

4 Compile crush map

[[email protected] getcrushmap]# crushtool -c decrushmap -o newcrushmap 

5 Inject crush map

[[email protected] getcrushmap]# ceph osd setcrushmap -i /opt/getcrushmap/newcrushmap set crush map 

[[email protected] getcrushmap]# ceph osd tree

ID WEIGHT TYPE NAME UP/DOWN REWEIGHT PRIMARY-AFFINITY

-6 0.00999 root stat 1 0.00999 osd.1 up 1.00000 1.00000 -5 0.00999 root ssd 0 0.00999 osd.0 up 1.00000 1.00000 -1 0.58498 root default -2 0.19499 host ceph-admin 2 0.19499 osd.2 up 1.00000 1.00000  -3 0.19499 host ceph-node1 0 0.19499 osd.0 up 1.00000 1.00000 -4 0.19499 host ceph-node2 1 0.19499 osd.1 up 1.00000 1.00000 # I already saw this when I checked the osd tree again The tree has changed. Added two buckets named stat and SSD

6 Create resource pool

[[email Protected] getcrushmap]# ceph osd pool create ssd_pool 8 8 pool 'ssd_pool' created [[emailprotected] getcrushmap] # ceph osd pool create stat_pool 8 8 pool 'stat_pool' created [[emailprotected] getcrushmap] # ceph osd dump|grep ssd pool 28 'ssd_pool' replicated size 3 min_size 2 crush_ruleset 0 object_hash rjenkins pg_num 8 pgp_num 8 last_change 2484 flags hashpspool stripe_width 0 [[emailprotected] getcrushmap]# ceph osd dump|grep stat pool 29 ' stat_pool' replicated size 3 min_size 2 crush_ruleset 0 object_hash rjenkins pg_num 8 pgp_num 8 last_change 2486 flags hashpspool stripe_width 0 < /span>

Note: The two The crush_ruleset of the resource pools ssd_pool and stat_pool are both 0, which needs to be modified below.

7 Modify resource pool storage rules

[[email protected] getcrushmap]# ceph osd pool set ssd_pool crush_ruleset 1 set pool 28 crush_ruleset to 1 [[email protected] getcrushmap]# ceph osd pool set stat_pool crush_ruleset 2 set pool 29 crush_ruleset to 2 [[emailprotected] getcrushmap]# ceph osd dump|grep ssd pool 28 'ssd_pool' replicated size 3 min_size 2 crush_ruleset 1 object_hash rjenkins pg_num 8 pgp_num 8 last_change 2488 flags hashpspool stripe_width < span class="hljs-number">0 [[emailprotected] getcrushmap]# ceph osd dump|grep stat pool 29 'stat_pool' replicated size 3 min_size 2 crush_ruleset 2 object_hash rjenkins pg_num 8 pgp_num 8 last_change 2491 flags hashpspool stripe_width 0 # The syntax of luminus version setting pool rule is [[email protected] ceph]# ceph osd pool set ssd crush_rule ssd < span class="hljs-keyword">set pool 2 crush_rule to ssd [[emailprotected] ceph]# ceph osd pool set stat crush_rule stat set pool 1 crush_rule to stat  span>  span> 

8 Validation

Before validation, see if there are any objects in ssd_pool and stat_pool p>

[[email protected] getcrushmap]# rados ls -p ssd_pool [[ email protected] getcrushmap]# rados ls -p stat_pool #There are no objects in these two resource pools< /span>

Use the rados command to add objects to the two resource pools

[[email protected] getcrushmap]# rados -p ssd_pool put test_object1 /etc/hosts [[emailprotected] getcrushmap]# rados -p stat_pool put test_object2 /etc/hosts [[emailprotected] getcrushmap]< span class="hljs-comment"># rados ls -p ssd_pool test_object1 [[emailprotected] getcrushmap]# rados ls -p sta t_pool test_object2 #Object added successfully

[[email protected] getcrushmap]# ceph osd map ssd_pool test_object1 osdmap e2493 pool 'ssd_pool' (28) object 'test_object1' -> pg 28.d5066e42 (28.2) -> up ([0], p0) acting ([0,1,2], p0) [[emailprotected] getcrushmap]# ceph osd map stat_pool test_object2 osdmap e2493 pool 'stat_pool' (29) object 'test_object2' -> pg 29.c5cfe5e9 (29.1) -> up ([ 1], p1) acting ([1,0,2], p1) < /span>

The above verification results can be seen , Test_object1 is stored in osd.0, and test_object2 is stored in osd.1. Achieve the expected purpose