基于Kubernetes的框架和应用系列之三：部署Ceph用于Kubernetes POD的永久存储

小灰灰 2022-10-01 13:55 190阅读 0赞

### 一、前言 ###

[Ceph][]是业界标准化的存储集成框架，支持多种底层存储，可以提供块存储、共享文件系统存储和对象存储，是Kubernetes存储标准化的未来集成方向。本文将基于Helm部署Ceph并向Kubernetes POD提供基于RBD的PVC

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Nsb3VkdnRlY2g_size_16_color_FFFFFF_t_70][]

转载自https://blog.csdn.net/cloudvtech

### 二、安装前准备工作 ###

**2.1 获取代码并打包成chart**

helm serve &
    helm repo add local http://localhost:8879/charts
    git clone https://github.com/ceph/ceph-helm
    cd ceph-helm/ceph
    make
    ls ceph/ceph-0.1.0.tgz

**2.2 安装依赖**

> yum install -y ceph-common
> 
> \# as node does config k8s internal DNS and ceph-mon is a NodePort service
> 
> echo "172.2.2.11 [ceph-mon.ceph.svc.cluster.local][]" > /etc/hosts

**2.3 Ceph的配置**

ceph-overrides.yaml

> network:
> 
>   public:   172.2.0.0/16 
> 
>   cluster:   172.2.0.0/16
> 
> osd\_devices:
> 
>   - name: dev-sdf
> 
>     device: /dev/sdf
> 
>     zap: "1"
> 
> storageclass:
> 
>   name: ceph-rbd
> 
>   pool: rbd
> 
>   user\_id: admin

上述配置的说明：

*  172.2.0.0/16是 k8s node所在IP range 
 *  作为Ceph存储的硬盘/dev/sdf，三台k8s节点都有这样一个设备，如果设备名称不同，后面node的label也需要变化

ls -l /dev/sdf
    brw-rw---- 1 root disk 8, 80 Oct 11 12:03 /dev/sdf

*  user\_id: admin，这里的 storageclass中的user\_id 如果不是 admin，则需要在 ceph 集群手动创建并在 kubernetes 中创建对应的 secret

**2.4 配置namespace和node label**

NS
    kubectl create namespace ceph
    
    RBAC
    kubectl create -f ~/ceph-helm/ceph/rbac.yaml
    
    LABEL
    kubectl label node k8s-node-01 ceph-mon=enabled ceph-mgr=enabled ceph-osd=enabled ceph-osd-device-dev-sdf=enabled
    kubectl label node k8s-node-02 ceph-mon=enabled ceph-osd=enabled ceph-osd-device-dev-sdf=enabled
    kubectl label node k8s-node-03 ceph-mon=enabled ceph-osd=enabled ceph-osd-device-dev-sdf=enabled

说明：

> 这里的 ceph-osd-dev-vdf 这个label 是根据 ceps-overrides.yaml中的 osd\_devices 的名称创建，如果每个节点多个 osd 盘，那么需要打相应个数的labels
> 
> ceph-mgr 只能以单副本运行

转载自https://blog.csdn.net/cloudvtech

### 三、安装Ceph ###

**3.1 修改value文件**

diff --git a/ceph/ceph/values.yaml b/ceph/ceph/values.yaml
    index 5831c53..617f53b 100644
    --- a/ceph/ceph/values.yaml
    +++ b/ceph/ceph/values.yaml
    @@ -254,8 +254,8 @@ ceph:
         mgr: true
       storage:
         # will have $NAMESPACE/{osd,mon} appended
    -    osd_directory: /var/lib/ceph-helm
    -    mon_directory: /var/lib/ceph-helm
    +    osd_directory: /var/lib/ceph
    +    mon_directory: /var/lib/ceph
         # use /var/log for fluentd to collect ceph log
         # mon_log: /var/log/ceph/mon
         # osd_log: /var/log/ceph/osd

**3.2 部署**

> **helm install --name=ceph ceph/ceph-0.1.0.tgz --namespace=ceph -f ceph-overrides.yaml**
> 
>  
> 
> LAST DEPLOYED: Thu Oct 11 04:05:45 2018
> 
> NAMESPACE: ceph
> 
> STATUS: DEPLOYED
> 
> RESOURCES:
> 
> ==> v1beta1/DaemonSet
> 
> NAME              DESIRED  CURRENT  READY  UP-TO-DATE  AVAILABLE  NODE SELECTOR                                     AGE
> 
> ceph-mon          3        3        3      3           3          ceph-mon=enabled                                  1h
> 
> ceph-osd-dev-sdf  3        3        3      3           3          ceph-osd-device-dev-sdf=enabled,ceph-osd=enabled  1h
> 
> ==> v1beta1/Deployment
> 
> NAME                  DESIRED  CURRENT  UP-TO-DATE  AVAILABLE  AGE
> 
> ceph-mds              1        1        1           0          1h
> 
> ceph-mgr              1        1        1           1          1h
> 
> ceph-mon-check        1        1        1           1          1h
> 
> ceph-rbd-provisioner  2        2        2           2          1h
> 
> ceph-rgw              1        1        1           0          1h
> 
> ==> v1/Job
> 
> NAME                                 DESIRED  SUCCESSFUL  AGE
> 
> ceph-mon-keyring-generator           1        1           1h
> 
> ceph-rgw-keyring-generator           1        1           1h
> 
> ceph-osd-keyring-generator           1        1           1h
> 
> ceph-mds-keyring-generator           1        1           1h
> 
> ceph-mgr-keyring-generator           1        1           1h
> 
> ceph-namespace-client-key-generator  1        1           1h
> 
> ceph-storage-keys-generator          1        1           1h
> 
> ==> v1/Pod(related)
> 
> NAME                                       READY  STATUS     RESTARTS  AGE
> 
> ceph-mon-565l5                             3/3    Running    0         1h
> 
> ceph-mon-ctr8c                             3/3    Running    0         1h
> 
> ceph-mon-rgs5p                             3/3    Running    0         1h
> 
> ceph-osd-dev-sdf-jqk86                     1/1    Running    0         1h
> 
> ceph-osd-dev-sdf-m5vc6                     1/1    Running    0         1h
> 
> ceph-osd-dev-sdf-pn6kt                     1/1    Running    0         1h
> 
> ceph-mds-666578c5f5-cw2fr                  0/1    Pending    0         1h
> 
> ceph-mgr-69c4b4d4bb-2hvtr                  1/1    Running    1         1h
> 
> ceph-mon-check-59499b664d-6jtrp            1/1    Running    0         1h
> 
> ceph-rbd-provisioner-5bc57f5f64-2wg9w      1/1    Running    0         1h
> 
> ceph-rbd-provisioner-5bc57f5f64-bmsmd      1/1    Running    0         1h
> 
> ceph-rgw-58c67497fb-llm5f                  0/1    Pending    0         1h
> 
> ceph-mon-keyring-generator-862pg           0/1    Completed  0         1h
> 
> ceph-rgw-keyring-generator-jvbcb           0/1    Completed  0         1h
> 
> ceph-osd-keyring-generator-slms7           0/1    Completed  0         1h
> 
> ceph-mds-keyring-generator-c8jzj           0/1    Completed  0         1h
> 
> ceph-mgr-keyring-generator-5wrl7           0/1    Completed  0         1h
> 
> ceph-namespace-client-key-generator-w2w7f  0/1    Completed  0         1h
> 
> ceph-storage-keys-generator-vzs5m          0/1    Completed  0         1h
> 
> ==> v1/Secret
> 
> NAME                    TYPE    DATA  AGE
> 
> ceph-keystone-user-rgw  Opaque  7     1h
> 
> ==> v1/ConfigMap
> 
> NAME              DATA  AGE
> 
> ceph-bin-clients  2     1h
> 
> ceph-bin          26    1h
> 
> ceph-etc          1     1h
> 
> ceph-templates    5     1h
> 
> ==> v1/StorageClass
> 
> NAME      PROVISIONER   AGE
> 
> ceph-rbd  [ceph.com/rbd][ceph.com_rbd]  1h
> 
> ==> v1/Service
> 
> NAME      TYPE       CLUSTER-IP    EXTERNAL-IP  PORT(S)   AGE
> 
> ceph-mon  ClusterIP  None          <none>       6789/TCP  1h
> 
> ceph-rgw  ClusterIP  10.96.22.221  <none>       8088/TCP  1h

**3.3 查看部署之后的信息**

[root@k8s-master-01 ceph-helm]# kubectl get pod -n ceph -o wide 
    NAME                                        READY     STATUS      RESTARTS   AGE       IP               NODE          NOMINATED NODE
    ceph-mds-666578c5f5-cw2fr                   0/1       Pending     0          1h        <none>           <none>        <none>
    ceph-mds-keyring-generator-c8jzj            0/1       Completed   0          1h        10.244.89.137    k8s-node-03   <none>
    ceph-mgr-69c4b4d4bb-2hvtr                   1/1       Running     1          1h        172.2.2.11       k8s-node-01   <none>
    ceph-mgr-keyring-generator-5wrl7            0/1       Completed   0          1h        10.244.89.172    k8s-node-03   <none>
    ceph-mon-565l5                              3/3       Running     0          1h        172.2.2.11       k8s-node-01   <none>
    ceph-mon-check-59499b664d-6jtrp             1/1       Running     0          1h        10.244.44.233    k8s-node-02   <none>
    ceph-mon-ctr8c                              3/3       Running     0          1h        172.2.2.12       k8s-node-02   <none>
    ceph-mon-keyring-generator-862pg            0/1       Completed   0          1h        10.244.154.203   k8s-node-01   <none>
    ceph-mon-rgs5p                              3/3       Running     0          1h        172.2.2.13       k8s-node-03   <none>
    ceph-namespace-client-key-generator-w2w7f   0/1       Completed   0          1h        10.244.44.206    k8s-node-02   <none>
    ceph-osd-dev-sdf-jqk86                      1/1       Running     0          1h        172.2.2.12       k8s-node-02   <none>
    ceph-osd-dev-sdf-m5vc6                      1/1       Running     0          1h        172.2.2.11       k8s-node-01   <none>
    ceph-osd-dev-sdf-pn6kt                      1/1       Running     0          1h        172.2.2.13       k8s-node-03   <none>
    ceph-osd-keyring-generator-slms7            0/1       Completed   0          1h        10.244.154.198   k8s-node-01   <none>
    ceph-rbd-provisioner-5bc57f5f64-2wg9w       1/1       Running     0          1h        10.244.44.205    k8s-node-02   <none>
    ceph-rbd-provisioner-5bc57f5f64-bmsmd       1/1       Running     0          1h        10.244.89.133    k8s-node-03   <none>
    ceph-rgw-58c67497fb-llm5f                   0/1       Pending     0          1h        <none>           <none>        <none>
    ceph-rgw-keyring-generator-jvbcb            0/1       Completed   0          1h        10.244.44.193    k8s-node-02   <none>
    ceph-storage-keys-generator-vzs5m           0/1       Completed   0          1h        10.244.154.236   k8s-node-01   <none>

说明：

> The MDS and RGW Pods are pending since we did not label any nodes with ceph-rgw=enabled or ceph-mds=enabled

获取StorageClass

kubectl get sc
    NAME                  PROVISIONER                                         AGE
    ceph-rbd              ceph.com/rbd                                        2h
    nfs-client            cluster.local/quiet-toucan-nfs-client-provisioner   20h

查看ceph-mon内部

kubectl exec -it ceph-mon-ctr8c  -n ceph -c ceph-mon -- ceph -s
      cluster:
        id:     676af649-2604-42ac-be5f-8cf37a712880
        health: HEALTH_WARN
                clock skew detected on mon.k8s-node-02, mon.k8s-node-03
     
      services:
        mon: 3 daemons, quorum k8s-node-01,k8s-node-02,k8s-node-03
        mgr: k8s-node-01(active)
        osd: 3 osds: 3 up, 3 in
     
      data:
        pools:   0 pools, 0 pgs
        objects: 0 objects, 0 bytes
        usage:   322 MB used, 32825 GB / 32826 GB avail
        pgs:

**3.4 配置key文件**

> **kubectl exec -it ceph-mon-ctr8c  -n ceph -c ceph-mon -- grep key /etc/ceph/ceph.client.admin.keyring |awk '\{printf "%s", $NF\}'|base64**
> 
> QVFBNXk3NWJBQUFBQUJBQXVicjRvNzVJa2xkN1g3YU5oQ1BGUHc9PQ0=
> 
> Edit the user secret present in the ceph namespace:
> 
> **kubectl edit secret pvc-ceph-client-key  -n ceph**
> 
> Add the base64 value to the key value with your own and save:
> 
> We are going to create a Pod that consumes a RBD in the default namespace. Copy the user secret from the ceph namespace to default:
> 
> **kubectl -n ceph get secrets/pvc-ceph-client-key -o json | jq '.metadata.namespace = "default"' | kubectl create -f -**
> 
> secret/pvc-ceph-client-key created

配置RBD池

kubectl -n ceph exec -ti ceph-mon-565l5 -c ceph-mon -- ceph osd pool create rbd 128
    pool 'rbd' created
    kubectl -n ceph exec -ti ceph-mon-565l5 -c ceph-mon -- rbd pool init rbd
    kubectl -n ceph exec -ti ceph-mon-565l5 -c ceph-mon -- ceph osd crush tunables hammer

转载自https://blog.csdn.net/cloudvtech

### 四、使用Ceph RBD作为POD的PVC ###

**4.1 创建PVC**

pvc-rbd.yaml

kind: PersistentVolumeClaim
    apiVersion: v1
    metadata:
      name: ceph-pvc
    spec:
      accessModes:
       - ReadWriteOnce
      resources:
        requests:
           storage: 20Gi
      storageClassName: ceph-rbd

查看PVC在Ceph内部对应的RBD信息

kubectl get pv | grep ceph
    pvc-4a8085ca-cd0d-11e8-9135-fa163ebda1b8   20Gi       RWO            Delete           Bound     default/ceph-pvc                     ceph-rbd                 1h
    
    kubectl -n ceph exec -ti ceph-mon-565l5 -c ceph-mon -- rbd ls
    kubernetes-dynamic-pvc-5c8953c2-cd0d-11e8-bb17-8a18da79c673
    
    kubectl -n ceph exec -ti ceph-mon-565l5 -c ceph-mon -- rbd info kubernetes-dynamic-pvc-5c8953c2-cd0d-11e8-bb17-8a18da79c673
    rbd image 'kubernetes-dynamic-pvc-5c8953c2-cd0d-11e8-bb17-8a18da79c673':
      size 20480 MB in 5120 objects
      order 22 (4096 kB objects)
      block_name_prefix: rbd_data.12f3238e1f29
      format: 2
      features: layering
      flags: 
      create_timestamp: Thu Oct 11 04:19:23 2018

**4.2 创建一个使用这个PVC的POD**

pod-with-rbd.yaml

kind: Pod
    apiVersion: v1
    metadata:
      name: ceph-rbd-pod
    spec:
      containers:
        - name: busybox
          image: busybox
          command:
            - sleep
            - "3600"
          volumeMounts:
          - mountPath: "/mnt/rbd"
            name: vol1
      volumes:
        - name: vol1
          persistentVolumeClaim:
            claimName: ceph-pvc

**4.3 查看部署结果**

[root@k8s-master-01 test-pv]# kubectl get pvc | grep ceph
    ceph-pvc                     Bound     pvc-4a8085ca-cd0d-11e8-9135-fa163ebda1b8   20Gi       RWO            ceph-rbd       1h
    
    kubectl describe pod ceph-rbd-pod
    …
    Volumes:
      vol1:
        Type:       PersistentVolumeClaim (a reference to a PersistentVolumeClaim in the same namespace)
        ClaimName:  ceph-pvc
        ReadOnly:   false
      default-token-khs2h:
        Type:        Secret (a volume populated by a Secret)
        SecretName:  default-token-khs2h
        Optional:    false
    …
    
    [root@k8s-master-01 test-pv]# kubectl exec -it ceph-rbd-pod sh
    / # mount | grep rbd
    /dev/rbd0 on /mnt/rbd type ext4 (rw,relatime,stripe=1024,data=ordered)
    / # df -h | grep rbd
    /dev/rbd0                19.6G     44.0M     19.5G   0% /mnt/rbd

**4.4 相关日志**

[root@k8s-master-01 ceph-helm]# kubectl -n ceph logs ceph-mon-565l5 -c cluster-log-tailer
    tail: can't open '/var/log/ceph/ceph.log': No such file or directory
    2018-10-11 04:02:24.250362 mon.k8s-node-01 unknown.0 - 0 :  [INF] mkfs 676af649-2604-42ac-be5f-8cf37a712880
    2018-10-11 04:02:14.222918 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 1 : cluster [INF] mon.k8s-node-01 calling monitor election
    tail: /var/log/ceph/ceph.log has appeared; following end of new file
    2018-10-11 04:02:19.227301 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 2 : cluster [INF] mon.k8s-node-01 is new leader, mons k8s-node-01,k8s-node-02 in quorum (ranks 0,1)
    2018-10-11 04:02:19.235731 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 3 : cluster [WRN] message from mon.1 was stamped 236.528097s in the future, clocks not synchronized
    2018-10-11 04:02:19.238536 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 4 : cluster [INF] mon.k8s-node-01 calling monitor election
    2018-10-11 04:02:24.241970 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 5 : cluster [INF] mon.k8s-node-01 is new leader, mons k8s-node-01,k8s-node-02 in quorum (ranks 0,1)
    2018-10-11 04:02:24.251072 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 7 : cluster [WRN] mon.1 172.2.2.12:6789/0 clock skew 236.521s > max 0.05s
    2018-10-11 04:02:24.251235 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 8 : cluster [WRN] message from mon.1 was stamped 236.529044s in the future, clocks not synchronized
    2018-10-11 04:02:24.252357 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 9 : cluster [INF] pgmap 0 pgs: ; 0 bytes data, 0 kB used, 0 kB / 0 kB avail
    2018-10-11 04:02:24.253631 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 10 : cluster [INF] HEALTH_ERR; no osds; 3 mons down, quorum  
    2018-10-11 04:02:24.253670 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 11 : cluster [INF] mon.k8s-node-01 calling monitor election
    2018-10-11 04:02:24.258318 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 12 : cluster [INF] mon.k8s-node-01 is new leader, mons k8s-node-01,k8s-node-02,k8s-node-03 in quorum (ranks 0,1,2)
    2018-10-11 04:02:24.261000 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 13 : cluster [WRN] mon.1 172.2.2.12:6789/0 clock skew 236.53s > max 0.05s
    2018-10-11 04:02:24.263522 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 14 : cluster [WRN] mon.2 172.2.2.13:6789/0 clock skew 177.015s > max 0.05s
    2018-10-11 04:02:24.310959 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 19 : cluster [WRN] Health check failed: clock skew detected on mon.k8s-node-02, mon.k8s-node-03 (MON_CLOCK_SKEW)
    2018-10-11 04:02:24.391378 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 20 : cluster [WRN] overall HEALTH_WARN clock skew detected on mon.k8s-node-02, mon.k8s-node-03
    2018-10-11 04:02:47.259003 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 34 : cluster [INF] Activating manager daemon k8s-node-01
    2018-10-11 04:02:47.822055 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 41 : cluster [INF] Manager daemon k8s-node-01 is now available
    2018-10-11 04:02:49.345659 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 44 : cluster [WRN] message from mon.1 was stamped 236.531430s in the future, clocks not synchronized
    2018-10-11 04:02:54.264590 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 46 : cluster [WRN] mon.2 172.2.2.13:6789/0 clock skew 177.019s > max 0.05s
    2018-10-11 04:02:54.264691 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 47 : cluster [WRN] mon.1 172.2.2.12:6789/0 clock skew 236.53s > max 0.05s
    2018-10-11 04:03:33.379645 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 82 : cluster [INF] osd.1 172.2.2.11:6801/53205 boot
    2018-10-11 04:03:47.829164 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 108 : cluster [INF] osd.0 172.2.2.13:6800/151522 boot
    2018-10-11 04:03:54.265810 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 114 : cluster [WRN] mon.2 172.2.2.13:6789/0 clock skew 177.019s > max 0.05s
    2018-10-11 04:03:54.265891 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 115 : cluster [WRN] mon.1 172.2.2.12:6789/0 clock skew 236.531s > max 0.05s
    2018-10-11 04:04:07.363697 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 129 : cluster [INF] osd.2 172.2.2.12:6800/39966 boot
    2018-10-11 04:04:55.365117 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 143 : cluster [WRN] message from mon.1 was stamped 236.532211s in the future, clocks not synchronized
    2018-10-11 04:05:24.266925 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 151 : cluster [WRN] mon.2 172.2.2.13:6789/0 clock skew 177.019s > max 0.05s
    2018-10-11 04:05:24.267013 mon.k8s-node-01 mon.0 172.2.2.11:6789/0 152 : cluster [WRN] mon.1 172.2.2.12:6789/0 clock skew 236.531s > max 0.05s

### **五、grafana监控** ###

Add monitoring

Log Into OSD pod and run
    ceph mgr module enable prometheus
    
    Edit ceph-mon service to bellow:
    apiVersion: v1
    kind: Service
    metadata:
      labels:
        k8s-app: ceph
      name: ceph-mon
      namespace: ceph
    spec:
      clusterIP: None
      ports:
      - name: tcp
        port: 6789
        protocol: TCP
        targetPort: 6789
      - name: metrics
        port: 9283
        protocol: TCP
        targetPort: 9283
      selector:
        application: ceph
        component: mon
        release_group: ceph
      sessionAffinity: None
      type: ClusterIP

Add servicemonitor  via ServiceMonitor-ceph.yaml

apiVersion: monitoring.coreos.com/v1
    kind: ServiceMonitor
    metadata:
      name: ceph
      namespace: monitoring
      labels:
        prometheus: kube-prometheus
    spec:
      jobLabel: k8s-ceph
      endpoints:
      - port: metrics
        interval: 10s
      selector:
        matchLabels:
          k8s-app: ceph
      namespaceSelector:
        matchNames:
        - ceph

Grafana dashboard for Ceph

### [https://grafana.com/grafana/dashboards/2842][https_grafana.com_grafana_dashboards_2842]![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Nsb3VkdnRlY2g_size_16_color_FFFFFF_t_70 1][] ###

### 转载自https://blog.csdn.net/cloudvtech ###

## ##

[Ceph]: https://my.oschina.net/hanhanztj/blog/488754
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Nsb3VkdnRlY2g_size_16_color_FFFFFF_t_70]: /images/20220118/57758ed677874e029e91a819e0c47584.png
[ceph-mon.ceph.svc.cluster.local]: http://ceph-mon.ceph.svc.cluster.local/
[ceph.com_rbd]: http://ceph.com/rbd
[https_grafana.com_grafana_dashboards_2842]: https://grafana.com/grafana/dashboards/2842
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Nsb3VkdnRlY2g_size_16_color_FFFFFF_t_70 1]: /images/20220118/c55b9be897104fb090a1c68581341b5f.png