Une fois rook-ceph installé et déployé, vous pouvez commencer à essayer d'utiliser StorageClass pour créer dynamiquement des pv.
Lorsqu'un middleware avec état est implémenté sur Kubernetes, StorageClass est essentiellement utilisé pour créer dynamiquement des pvs (pour les applications cloud, il n'y a pas tellement de soucis, les disques cloud sont faciles à utiliser, mais pour l'auto-apprentissage et la pratique, Ceph est plus fiable). , essayons la puissance de la création dynamique de PV pour nous préparer à l'utiliser plus tard pour jouer avec redis, zookeeper et elasticsearch.
1. Créez StorageClass et un pool de stockage
kubectl create -f rook/deploy/examples/csi/rbd/storageclass.yaml
Afficher le cephblockpool et StorageClass créés
kubectl get cephblockpool -n rook-ceph
kubectl get sc
Le résultat est le suivant :
Le contenu de rook/deploy/examples/csi/rbd/storageclass.yaml est le suivant :
apiVersion: ceph.rook.io/v1
kind: CephBlockPool
metadata:
name: replicapool
namespace: rook-ceph # namespace:cluster
spec:
failureDomain: host
replicated:
size: 2
# Disallow setting pool with replica 1, this could lead to data loss without recovery.
# Make sure you're *ABSOLUTELY CERTAIN* that is what you want
requireSafeReplicaSize: true
# gives a hint (%) to Ceph in terms of expected consumption of the total cluster capacity of a given pool
# for more info: https://docs.ceph.com/docs/master/rados/operations/placement-groups/#specifying-expected-pool-size
#targetSizeRatio: .5
---
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
name: rook-ceph-block
# Change "rook-ceph" provisioner prefix to match the operator namespace if needed
provisioner: rook-ceph.rbd.csi.ceph.com
parameters:
# clusterID is the namespace where the rook cluster is running
# If you change this namespace, also change the namespace below where the secret namespaces are defined
clusterID: rook-ceph # namespace:cluster
# If you want to use erasure coded pool with RBD, you need to create
# two pools. one erasure coded and one replicated.
# You need to specify the replicated pool here in the `pool` parameter, it is
# used for the metadata of the images.
# The erasure coded pool must be set as the `dataPool` parameter below.
#dataPool: ec-data-pool
pool: replicapool
# (optional) mapOptions is a comma-separated list of map options.
# For krbd options refer
# https://docs.ceph.com/docs/master/man/8/rbd/#kernel-rbd-krbd-options
# For nbd options refer
# https://docs.ceph.com/docs/master/man/8/rbd-nbd/#options
# mapOptions: lock_on_read,queue_depth=1024
# (optional) unmapOptions is a comma-separated list of unmap options.
# For krbd options refer
# https://docs.ceph.com/docs/master/man/8/rbd/#kernel-rbd-krbd-options
# For nbd options refer
# https://docs.ceph.com/docs/master/man/8/rbd-nbd/#options
# unmapOptions: force
# (optional) Set it to true to encrypt each volume with encryption keys
# from a key management system (KMS)
# encrypted: "true"
# (optional) Use external key management system (KMS) for encryption key by
# specifying a unique ID matching a KMS ConfigMap. The ID is only used for
# correlation to configmap entry.
# encryptionKMSID: <kms-config-id>
# RBD image format. Defaults to "2".
imageFormat: "2"
# RBD image features
# Available for imageFormat: "2". Older releases of CSI RBD
# support only the `layering` feature. The Linux kernel (KRBD) supports the
# full complement of features as of 5.4
# `layering` alone corresponds to Ceph's bitfield value of "2" ;
# `layering` + `fast-diff` + `object-map` + `deep-flatten` + `exclusive-lock` together
# correspond to Ceph's OR'd bitfield value of "63". Here we use
# a symbolic, comma-separated format:
# For 5.4 or later kernels:
#imageFeatures: layering,fast-diff,object-map,deep-flatten,exclusive-lock
# For 5.3 or earlier kernels:
imageFeatures: layering
# The secrets contain Ceph admin credentials. These are generated automatically by the operator
# in the same namespace as the cluster.
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
# Specify the filesystem type of the volume. If not specified, csi-provisioner
# will set default as `ext4`. Note that `xfs` is not recommended due to potential deadlock
# in hyperconverged settings where the volume is mounted on the same node as the osds.
csi.storage.k8s.io/fstype: ext4
# uncomment the following to use rbd-nbd as mounter on supported nodes
# **IMPORTANT**: CephCSI v3.4.0 onwards a volume healer functionality is added to reattach
# the PVC to application pod if nodeplugin pod restart.
# Its still in Alpha support. Therefore, this option is not recommended for production use.
#mounter: rbd-nbd
allowVolumeExpansion: true
reclaimPolicy: Delete
2. Créez un StatefulSet de nginx et utilisez storageclass pour créer dynamiquement un pv et le lier au pod avec état /usr/share/nginx/html. Chaque pod doit avoir son propre pv. Pour Redis, zookeeper et elasticsearch, storageClass est utilisé pour créer dynamiquement des pv.
kubectl apply -f test_volumnClainTemplates.yaml
Affichez la commande comme suit :
kubectl get po -l app=nginx
kubectl get pvc
Le résultat est le suivant :
Le contenu de test_volumnClainTemplates.yaml est le suivant :
apiVersion: v1
kind: Service
metadata:
name: nginx
labels:
app: nginx
spec:
ports:
- port: 80
name: web
clusterIP: None
selector:
app: nginx
---
apiVersion: apps/v1
kind: StatefulSet
metadata:
name: web
spec:
selector:
matchLabels:
app: nginx
serviceName: "nginx"
replicas: 2
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: 200M