【kubernetes/k8s概念】 rook design分析

1. Ceph Cluster CRD

apiVersion: ceph.rook.io/v1
kind: CephCluster
metadata:
  name: rook-ceph
  namespace: rook-ceph
spec:
  cephVersion:
    # see the "Cluster Settings" section below for more details on which image of ceph to run
    image: ceph/ceph:v14.2.1-20190430
  dataDirHostPath: /var/lib/rook
  mon:
    count: 3
    allowMultiplePerNode: true
  storage:
    useAllNodes: true
    useAllDevices: true

    1.1 cephVersion: 版本信息

          image

          allowUnsupported：生产环境建议false

    1.2 dataDirHostPath: hostPath方式的挂载路径，一般为/var/lib/rook

         如果创建新cluster，先前数据必须清除，否则mon启动失败

    1.3 mon：

          count：启动mon pod的个数 1 <= count <= 9，默认为3，

          preferredCount：主要是扩容Mon个数使用的

          allowMultiplePerNode：是否允许一个node上跑多个mon，默认为false

    1.4 dashboard：集群dashboard，可以查看集群状态

    1.5 resources：pod资源请求与限制，cpu与mem

    1.6 storage：存储配置信息

          useAllNodes： true / false，是否所有的节点都用来做存储，如果指定节点存储设置为false，生产环境建议设置false

         nodes：配置单个存储节点，需要useAllNodes设置为false

               name： kubernetes匹配kubernetes.io/hostname 

    1.7 useAllDevices：不建议使用true，如果deviceFilter设置，将会被覆盖掉

    1.8 deviceFilter：正则表达，如果一个节点指定使用device，则该选项被忽略

    1.9 devices：

    1.10 config：

            metadataDevice：可以选择使用设备存储metadata，比如SSD

            storeType：filestore / bluestore（default），

           databaseSizeMB：bluestore database

            walSizeMB：bluestore write ahead log (WAL)

            journalSizeMB：filestore journal.

            osdsPerDevice：

            encryptedDevice：

             

示例：

apiVersion: ceph.rook.io/v1
kind: CephCluster
metadata:
  name: rook-ceph
  namespace: rook-ceph
spec:
  cephVersion:
    image: ceph/ceph:v14.2.1-20190430
  dataDirHostPath: /var/lib/rook
  mon:
    count: 3
    allowMultiplePerNode: true
  dashboard:
    enabled: true
  # cluster level storage configuration and selection
  storage:
    useAllNodes: false
    useAllDevices: false
    deviceFilter:
    location:
    config:
      metadataDevice:
      databaseSizeMB: "1024" # this value can be removed for environments with normal sized disks (100 GB or larger)
      journalSizeMB: "1024"  # this value can be removed for environments with normal sized disks (20 GB or larger)
    nodes:
    - name: "172.17.4.101"
      directories:         # specific directories to use for storage can be specified for each node
      - path: "/rook/storage-dir"
    - name: "172.17.4.201"
      devices:             # specific devices to use for storage can be specified for each node
      - name: "sdb"
      - name: "sdc"
      config:         # configuration can be specified at the node level which overrides the cluster level config
        storeType: bluestore
    - name: "172.17.4.301"
      deviceFilter: "^sd."

 

2. Ceph Block Pool CRD

   Rook allows creation and customization of storage pools through the custom resource definitions (CRDs). The following settings are available for pools.

Replicated: 数据副本数量，至少需要的osd数量，如果设置erasureCoded就不能设置

erasureCoded：

• dataChunks: Number of chunks to divide the original object into
• codingChunks: Number of redundant chunks to store

failureDomain：

apiVersion: ceph.rook.io/v1
kind: CephBlockPool
metadata:
  name: replicapool
  namespace: rook-ceph
spec:
  failureDomain: host
  replicated:
    size: 3
  deviceClass: hdd

 

 

参考：

   https://github.com/rook/rook/blob/master/Documentation/ceph-cluster-crd.md

   https://github.com/rook/rook/blob/master/Documentation/ceph-pool-crd.md