06 云原生 RBD 块存储（转载）

标签：原生 rook 06 name ceph wordpress mysql RBD root

云原生 RBD 块存储

云原生 `RBD` 块存储

`RBD` 块存储概述

什么是块存储：A block is a sequence of bytes (often 512). Block-based storage interfaces are a mature and common way to store data on media including HDDs, SSDs, CDs, floppy disks, and even tape.

EBS
CBS
FC块

Thin-provisioned （受分配，使用多少分配多少，慢慢扩大）
Images up to 16 exabytes （单个镜像最大16EB）
Configurable striping（可配置切片）
In-memory caching （内存缓存）
Snapshots（支持快照）
Copy-on-write cloning（快照克隆）
Kernel driver support（内核支持）
KVM/libvirt support（kvm/librirt支持）
Back-end for cloud solutions（后端支持云解决方案）
Incremental backup（增量备份）
Disaster recovery (multisite asynchronous replication)（灾难恢复）

`RBD` 与容器对接

三种方式

volume: 卷的存储方式，支持多种驱动，FC，EBS，Ceph等
PV/PVC : Persistent Volume 和 Persistent Volume Claim
StorageClass : 包含静态+动态两种
- 管理员定义好 provioner
- 终端用户通过 PVC 关联

`Ceph` 对接回顾

参考 Ceph 官方文档

Ceph 和 kubernetes 的对接过程涉及到 pool 的创建， Ceph 认证信息，配置文件， CSI 驱动部署， StorageClass 创建等一系列过程。配置过程有一定的难度，如果对 Ceph 不熟悉的同学，对接可能有一定难度，而 Rook 则将这些配置过程简化，以云原生的方式实现对接，其默认已经继承好相关驱动，直接通过 kubernetes 创建 storageclass 即可。

`CSI` 驱动信息

包含 rbd 和 cephfs 的驱动，csi-cephfsplugin 和 csi-rbdplugin
驱动由 provisioner 和 plugin 组成

RBD块存储类

RBD 相关的存储驱动和 provisioner 安装 rook 时候已经创建好，因此接下来只需要直接对接即可， Rook 提供了两种对接的方式：

FlexVolume
CSI

其中 Flex 的方式比较老，默认驱动未安装，需要安装才可以对接，逐步淘汰，不建议使用，推荐使用 CSI 的对接方式

[root@m1 ceph]# cat csi/rbd/storageclass.yaml

apiVersion: ceph.rook.io/v1
kind: CephBlockPool
metadata:
  name: replicapool
  namespace: rook-ceph
spec:
  failureDomain: host
  replicated:
    size: 3
    requireSafeReplicaSize: true
---
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
   name: rook-ceph-block
provisioner: rook-ceph.rbd.csi.ceph.com
parameters:
    clusterID: rook-ceph # namespace:cluster
    pool: replicapool
    imageFormat: "2"
    imageFeatures: layering

    csi.storage.k8s.io/provisioner-secret-name: rook-csi-rbd-provisioner
    csi.storage.k8s.io/provisioner-secret-namespace: rook-ceph # namespace:cluster
    csi.storage.k8s.io/controller-expand-secret-name: rook-csi-rbd-provisioner
    csi.storage.k8s.io/controller-expand-secret-namespace: rook-ceph # namespace:cluster
    csi.storage.k8s.io/node-stage-secret-name: rook-csi-rbd-node
    csi.storage.k8s.io/node-stage-secret-namespace: rook-ceph # namespace:cluster
    csi.storage.k8s.io/fstype: ext4
allowVolumeExpansion: true
reclaimPolicy: Delete

# 执行资源清单
[root@m1 ceph]# kubectl apply -f csi/rbd/storageclass.yaml
cephblockpool.ceph.rook.io/replicapool created
storageclass.storage.k8s.io/rook-ceph-block created

校验 `pool` 安装情况

配置 ceph 客户端认证

[root@m1 ceph]# kubectl -n rook-ceph exec -it rook-ceph-tools-77bf5b9b7d-9pq6m -- cat /etc/ceph/ceph.conf | tee /etc/ceph/ceph.conf
[global]
mon_host = 10.68.231.222:6789,10.68.163.216:6789,10.68.61.127:6789

[client.admin]
keyring = /etc/ceph/keyring

[root@m1 ceph]# kubectl -n rook-ceph exec -it rook-ceph-tools-77bf5b9b7d-9pq6m -- cat /etc/ceph/keyring | tee /etc/ceph/keyring
[client.admin]
key = AQDm435jUMuCKhAAXXPqMX08cLyjs/EOvchkzA==

[root@m1 ceph]# ceph -s
  cluster:
    id:     17a413b5-f140-441a-8b35-feec8ae29521
    health: HEALTH_OK
 
  services:
    mon: 3 daemons, quorum a,b,c (age 2h)
    mgr: a(active, since 6h)
    osd: 5 osds: 5 up (since 6h), 5 in (since 6h)
 
  data:
    pools:   1 pools, 1 pgs
    objects: 0 objects, 0 B
    usage:   5.0 GiB used, 245 GiB / 250 GiB avail
    pgs:     1 active+clean

校验 pool

[root@m1 ceph]# ceph osd lspools
1 device_health_metrics
2 replicapool

[root@m1 ceph]# ceph osd pool get replicapool size
size: 3

校验 `StorageClass`

[root@m1 ceph]# kubectl get sc
NAME              PROVISIONER                  RECLAIMPOLICY   VOLUMEBINDINGMODE   ALLOWVOLUMEEXPANSION   AGE
rook-ceph-block   rook-ceph.rbd.csi.ceph.com   Delete          Immediate           true                   2m56s

容器 `PVC` 调用存储

创建好 storageclass 之后，我们就可以通过 PVC 向 storageclass 申请容量空间了， PVC 会自动和 storageclass 完成存储容量的创建过程，包括自动创建 PV ， PV 与后端存储自动完成 RBD 块存储的创建，整个过程不需要我们关心，均通过 storageclass 和驱动自动完成，我们只需要关注使用即可，如下是一个 wordpress 博客应用连接 MySQL 数据库的一个云原生应用的范例

`wordpress` 资源清单

[root@m1 ceph]# cd ../
[root@m1 kubernetes]# cat wordpress.yaml 

apiVersion: v1
kind: Service
metadata:
  name: wordpress
  labels:
    app: wordpress
spec:
  ports:
  - port: 80
  selector:
    app: wordpress
    tier: frontend
  type: LoadBalancer
---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: wp-pv-claim
  labels:
    app: wordpress
spec:
  storageClassName: rook-ceph-block
  accessModes:
  - ReadWriteOnce
  resources:
    requests:
      storage: 20Gi
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: wordpress
  labels:
    app: wordpress
    tier: frontend
spec:
  selector:
    matchLabels:
      app: wordpress
      tier: frontend
  strategy:
    type: Recreate
  template:
    metadata:
      labels:
        app: wordpress
        tier: frontend
    spec:
      containers:
      - image: wordpress:4.6.1-apache
        name: wordpress
        env:
        - name: WORDPRESS_DB_HOST
          value: wordpress-mysql
        - name: WORDPRESS_DB_PASSWORD
          value: changeme
        ports:
        - containerPort: 80
          name: wordpress
        volumeMounts:
        - name: wordpress-persistent-storage
          mountPath: /var/www/html
      volumes:
      - name: wordpress-persistent-storage
        persistentVolumeClaim:
          claimName: wp-pv-claim

`MySQL` 资源清单

[root@m1 kubernetes]# cat mysql.yaml 

apiVersion: v1
kind: Service
metadata:
  name: wordpress-mysql
  labels:
    app: wordpress
spec:
  ports:
    - port: 3306
  selector:
    app: wordpress
    tier: mysql
  clusterIP: None
---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: mysql-pv-claim
  labels:
    app: wordpress
spec:
  storageClassName: rook-ceph-block
  accessModes:
  - ReadWriteOnce
  resources:
    requests:
      storage: 20Gi
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: wordpress-mysql
  labels:
    app: wordpress
    tier: mysql
spec:
  selector:
    matchLabels:
      app: wordpress
      tier: mysql
  strategy:
    type: Recreate
  template:
    metadata:
      labels:
        app: wordpress
        tier: mysql
    spec:
      containers:
      - image: mysql:5.6
        name: mysql
        env:
        - name: MYSQL_ROOT_PASSWORD
          value: changeme
        ports:
        - containerPort: 3306
          name: mysql
        volumeMounts:
        - name: mysql-persistent-storage
          mountPath: /var/lib/mysql
      volumes:
      - name: mysql-persistent-storage
        persistentVolumeClaim:
          claimName: mysql-pv-claim

创建 wordpress 和 mysql

[root@m1 kubernetes]# kubectl get pods
NAME                               READY   STATUS    RESTARTS   AGE
wordpress-7b989dbf57-cvqtk         1/1     Running   0          6m25s
wordpress-mysql-6965fc8cc8-mt2p9   1/1     Running   0          6m20s

[root@m1 kubernetes]# kubectl get pvc
NAME             STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS      AGE
mysql-pv-claim   Bound    pvc-2bcd6af2-31e3-40b8-add9-476b167399be   20Gi       RWO            rook-ceph-block   29s
wp-pv-claim      Bound    pvc-2fadab42-abd6-49e0-b53f-b587f3b8f95d   20Gi       RWO            rook-ceph-block   34s

[root@m1 kubernetes]# kubectl get pv
NAME                                       CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS   CLAIM                    STORAGECLASS      REASON   AGE
pvc-2bcd6af2-31e3-40b8-add9-476b167399be   20Gi       RWO            Delete           Bound    default/mysql-pv-claim   rook-ceph-block            31s
pvc-2fadab42-abd6-49e0-b53f-b587f3b8f95d   20Gi       RWO            Delete           Bound    default/wp-pv-claim      rook-ceph-block            35s

`PVC` 调用逻辑

PVC 会完成一系列的出对接过程，包含有什么动作。 PVC —> storageclass 申请容量 —> 创建 PV ——> 向 Ceph 申请 RBD 块，完成和 Ceph 对接

查看PVC创建情况

[root@m1 kubernetes]# kubectl get pvc
NAME             STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS      AGE
mysql-pv-claim   Bound    pvc-2bcd6af2-31e3-40b8-add9-476b167399be   20Gi       RWO            rook-ceph-block   8m14s
wp-pv-claim      Bound    pvc-2fadab42-abd6-49e0-b53f-b587f3b8f95d   20Gi       RWO            rook-ceph-block   8m19s

查看详情

[root@m1 kubernetes]# kubectl get pvc mysql-pv-claim -o yaml
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  ......
  name: mysql-pv-claim
  namespace: default
spec:
  accessModes:
  - ReadWriteOnce
  resources:
    requests:
      storage: 20Gi
  storageClassName: rook-ceph-block
  volumeMode: Filesystem
  volumeName: pvc-2bcd6af2-31e3-40b8-add9-476b167399be
status:
  accessModes:
  - ReadWriteOnce
  capacity:
    storage: 20Gi
  phase: Bound

`PVC` 会自动创建 `PV`

PV 信息

[root@m1 kubernetes]# kubectl get pv
NAME                                       CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS   CLAIM                    STORAGECLASS      REASON   AGE
pvc-2bcd6af2-31e3-40b8-add9-476b167399be   20Gi       RWO            Delete           Bound    default/mysql-pv-claim   rook-ceph-block            10m
pvc-2fadab42-abd6-49e0-b53f-b587f3b8f95d   20Gi       RWO            Delete           Bound    default/wp-pv-claim      rook-ceph-block            10m

详细的 PV 信息

[root@m1 kubernetes]# kubectl get pv pvc-2bcd6af2-31e3-40b8-add9-476b167399be -o yaml
apiVersion: v1
kind: PersistentVolume
metadata:
  ......
  name: pvc-2bcd6af2-31e3-40b8-add9-476b167399be
spec:
  accessModes:
  - ReadWriteOnce
  capacity:
    storage: 20Gi
  claimRef:
    apiVersion: v1
    kind: PersistentVolumeClaim
    name: mysql-pv-claim
    namespace: default
    resourceVersion: "502998"
    uid: 2bcd6af2-31e3-40b8-add9-476b167399be
  csi:
    controllerExpandSecretRef:
      name: rook-csi-rbd-provisioner
      namespace: rook-ceph
    driver: rook-ceph.rbd.csi.ceph.com
    fsType: ext4
    nodeStageSecretRef:
      name: rook-csi-rbd-node
      namespace: rook-ceph
    volumeAttributes:
      clusterID: rook-ceph
      imageFeatures: layering
      imageFormat: "2"
      imageName: csi-vol-10342079-6beb-11ed-b5c4-6efb82c232c4   # 关联 rbd 信息
      journalPool: replicapool
      pool: replicapool
      radosNamespace: ""
      storage.kubernetes.io/csiProvisionerIdentity: 1669260272979-8081-rook-ceph.rbd.csi.ceph.com
    volumeHandle: 0001-0009-rook-ceph-0000000000000002-10342079-6beb-11ed-b5c4-6efb82c232c4
  persistentVolumeReclaimPolicy: Delete
  storageClassName: rook-ceph-block
  volumeMode: Filesystem
status:
  phase: Bound

`PV` 会完成和 `Ceph` 的对接，自动创建 `RBD` 块存储空间，期间由 `plugin` 驱动完成创建

rbd 信息

[root@m1 kubernetes]# rbd -p replicapool ls
csi-vol-0d43155e-6beb-11ed-b5c4-6efb82c232c4
csi-vol-10342079-6beb-11ed-b5c4-6efb82c232c4

mysql 使用 rbd 块信息

[root@m1 kubernetes]# rbd -p replicapool info csi-vol-10342079-6beb-11ed-b5c4-6efb82c232c4
rbd image 'csi-vol-10342079-6beb-11ed-b5c4-6efb82c232c4':
        size 20 GiB in 5120 objects
        order 22 (4 MiB objects)
        snapshot_count: 0
        id: 12fae9f8d2613
        block_name_prefix: rbd_data.12fae9f8d2613
        format: 2
        features: layering
        op_features: 
        flags: 
        create_timestamp: Thu Nov 24 19:28:05 2022
        access_timestamp: Thu Nov 24 19:28:05 2022
        modify_timestamp: Thu Nov 24 19:28:05 2022

`Wordpress` 功能验证

wordpress 和 mysql 实际存储空间存放在 Ceph RBD 块中，通过 nodePort 的登录 MySQL ，验证 wordpress 的安装情况，首先需要核对 pods 部署是否正常，确保均 Running

[root@m1 kubernetes]# kubectl get pods
NAME                               READY   STATUS    RESTARTS   AGE
wordpress-7b989dbf57-cvqtk         1/1     Running   0          17m
wordpress-mysql-6965fc8cc8-mt2p9   1/1     Running   0          17m

wordpress 通过 service 暴露服务，默认类型为 LoadBalancer ， LoadBalancer 依赖于 NodePort ，因此可以直接通过 NodePort 的形式访问，通过任意一个节点的 NodePort 即可访问到 wordpress 的应用。

[root@m1 kubernetes]# kubectl get svc
NAME              TYPE           CLUSTER-IP      EXTERNAL-IP   PORT(S)        AGE
kubernetes        ClusterIP      10.68.0.1       <none>        443/TCP        2d3h
wordpress         LoadBalancer   10.68.235.228   <pending>     80:36063/TCP   19m
wordpress-mysql   ClusterIP      None            <none>        3306/TCP       19m

查看 rbd 映射情况

[root@m1 kubernetes]# kubectl get pods -o wide
NAME                               READY   STATUS    RESTARTS   AGE   IP            NODE              NOMINATED NODE   READINESS GATES
wordpress-7b989dbf57-cvqtk         1/1     Running   0          41m   172.20.4.27   192.168.100.136   <none>           <none>
wordpress-mysql-6965fc8cc8-mt2p9   1/1     Running   0          41m   172.20.4.28   192.168.100.136   <none>           <none>

[root@m1 kubernetes]# ssh n3
Last login: Thu Nov 24 20:07:31 2022 from m1

[root@n3 ~]# rbd showmapped
2022-11-24 20:09:07.150816 7f5daf0d6d80 -1 did not load config file, using default settings.
id pool        image                                        snap device    
0  replicapool csi-vol-0d43155e-6beb-11ed-b5c4-6efb82c232c4 -    /dev/rbd0 
1  replicapool csi-vol-10342079-6beb-11ed-b5c4-6efb82c232c4 -    /dev/rbd1 

[root@n3 ~]# exit

存储持久化模板

PVC 使用模式适用于单个 pods 容器，如多个 pods 都需要有各自的存储如何实现，需要借助于 StatefulSet 的 volumeClaimTemplates 功能，实现每个 pods 均有各自的存储。

[root@m1 kubernetes]# cat << EOF > sts-test.yaml
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: web
spec:
  selector:
    matchLabels:
      app: nginx # has to match .spec.template.metadata.labels
  serviceName: "nginx"
  replicas: 3 # by default is 1
  template:
    metadata:
      labels:
        app: nginx
    spec:
      terminationGracePeriodSeconds: 10
      containers:
      - name: nginx
        image: nginx
        ports:
        - containerPort: 80
          name: web
        volumeMounts:
        - name: www
          mountPath: /usr/share/nginx/html
  volumeClaimTemplates:
  - metadata:
      name: www
    spec:
      accessModes: [ "ReadWriteOnce" ]
      storageClassName: "rook-ceph-block"
      resources:
        requests:
          storage: 10Gi
EOF

部署服务查看 pv pvc 情况

[root@m1 kubernetes]# kubectl apply -f sts-test.yaml 
statefulset.apps/web created

[root@m1 kubernetes]# kubectl get pods  
NAME                               READY   STATUS    RESTARTS   AGE
web-0                              1/1     Running   0          103s
web-1                              1/1     Running   0          65s
web-2                              1/1     Running   0          51s
wordpress-7b989dbf57-cvqtk         1/1     Running   0          14h
wordpress-mysql-6965fc8cc8-mt2p9   1/1     Running   0          14h

[root@m1 kubernetes]# kubectl get pvc
NAME             STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS      AGE
mysql-pv-claim   Bound    pvc-2bcd6af2-31e3-40b8-add9-476b167399be   20Gi       RWO            rook-ceph-block   14h
wp-pv-claim      Bound    pvc-2fadab42-abd6-49e0-b53f-b587f3b8f95d   20Gi       RWO            rook-ceph-block   14h
www-web-0        Bound    pvc-9d32f5ff-174a-461f-9f3c-e0f0f5e60cc8   10Gi       RWO            rook-ceph-block   83s
www-web-1        Bound    pvc-af0e2916-ec93-4f55-871f-0d008c0394e0   10Gi       RWO            rook-ceph-block   45s
www-web-2        Bound    pvc-174fb859-91ad-49e2-8e44-d7ee64645e7e   10Gi       RWO            rook-ceph-block   31s

[root@m1 kubernetes]# kubectl get pv
NAME                                       CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS   CLAIM                    STORAGECLASS      REASON   AGE
pvc-174fb859-91ad-49e2-8e44-d7ee64645e7e   10Gi       RWO            Delete           Bound    default/www-web-2        rook-ceph-block            32s
pvc-2bcd6af2-31e3-40b8-add9-476b167399be   20Gi       RWO            Delete           Bound    default/mysql-pv-claim   rook-ceph-block            14h
pvc-2fadab42-abd6-49e0-b53f-b587f3b8f95d   20Gi       RWO            Delete           Bound    default/wp-pv-claim      rook-ceph-block            14h
pvc-9d32f5ff-174a-461f-9f3c-e0f0f5e60cc8   10Gi       RWO            Delete           Bound    default/www-web-0        rook-ceph-block            84s
pvc-af0e2916-ec93-4f55-871f-0d008c0394e0   10Gi       RWO            Delete           Bound    default/www-web-1        rook-ceph-block            46s

标签：原生,rook,06,name,ceph,wordpress,mysql,RBD,root
From： https://www.cnblogs.com/evescn/p/16924195.html

06 云原生 RBD 块存储（转载）

云原生 `RBD` 块存储

`RBD` 块存储概述

`RBD` 与容器对接

三种方式

`Ceph` 对接回顾

`CSI` 驱动信息

RBD块存储类

校验 `pool` 安装情况

校验 `StorageClass`

容器 `PVC` 调用存储

`wordpress` 资源清单

`MySQL` 资源清单

创建 wordpress 和 mysql

`PVC` 调用逻辑

`PVC` 会自动创建 `PV`

`PV` 会完成和 `Ceph` 的对接，自动创建 `RBD` 块存储空间，期间由 `plugin` 驱动完成创建

`Wordpress` 功能验证

存储持久化模板

相关文章

赞助商

阅读排行

06 云原生 RBD 块存储（转载）

云原生 RBD 块存储

RBD 块存储概述

RBD 与容器对接

三种方式

Ceph 对接回顾

CSI 驱动信息

RBD块存储类

校验 pool 安装情况

校验 StorageClass

容器 PVC 调用存储

wordpress 资源清单

MySQL 资源清单

创建 wordpress 和 mysql

PVC 调用逻辑

PVC 会自动创建 PV

PV 会完成和 Ceph 的对接，自动创建 RBD 块存储空间，期间由 plugin 驱动完成创建

Wordpress 功能验证

存储持久化模板

相关文章

赞助商

阅读排行

云原生 `RBD` 块存储

`RBD` 块存储概述

`RBD` 与容器对接

`Ceph` 对接回顾

`CSI` 驱动信息

校验 `pool` 安装情况

校验 `StorageClass`

容器 `PVC` 调用存储

`wordpress` 资源清单

`MySQL` 资源清单

`PVC` 调用逻辑

`PVC` 会自动创建 `PV`

`PV` 会完成和 `Ceph` 的对接，自动创建 `RBD` 块存储空间，期间由 `plugin` 驱动完成创建

`Wordpress` 功能验证