在k8s上部署ES集群

1、配置storageclass，用于动态创建pvc，并自动绑定pv

[root@master1 tmp]# cat sc.yaml
kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
  name: local-storage
provisioner: kubernetes.io/no-provisioner
volumeBindingMode: WaitForFirstConsumer 

执行一下：

kubectl apply -f sc.yaml

2、创建PV

[root@master1 tmp]# cat pv.yaml 
apiVersion: v1
kind: PersistentVolume
metadata:
  name: local-storage-pv-1
  namespace: elasticsearch
  labels:
    name: local-storage-pv-1
spec:
  capacity:
    storage: 1Gi
  accessModes:
  - ReadWriteonce
  persistentVolumeReclaimPolicy: Retain
  storageClassName: local-storage
  local:
    path: /data/es
  nodeAffinity:
    required:
      nodeSelectorTerms:
      - matchexpressions:
        - key: kubernetes.io/hostname
          operator: In
          values:
          - master1
---
apiVersion: v1
kind: PersistentVolume
metadata:
  name: local-storage-pv-2
  namespace: elasticsearch
  labels:
    name: local-storage-pv-2
spec:
  capacity:
    storage: 1Gi
  accessModes:
  - ReadWriteonce
  persistentVolumeReclaimPolicy: Retain
  storageClassName: local-storage
  local:
    path: /data/es
  nodeAffinity:
    required:
      nodeSelectorTerms:
      - matchexpressions:
        - key: kubernetes.io/hostname
          operator: In
          values:
          - master2
---
apiVersion: v1
kind: PersistentVolume
metadata:
  name: local-storage-pv-3
  namespace: elasticsearch
  labels:
    name: local-storage-pv-3
spec:
  capacity:
    storage: 1Gi
  accessModes:
  - ReadWriteonce
  persistentVolumeReclaimPolicy: Retain
  storageClassName: local-storage
  local:
    path: /data/es
  nodeAffinity:
    required:
      nodeSelectorTerms:
      - matchexpressions:
        - key: kubernetes.io/hostname
          operator: In
          values:
          - master3
---
apiVersion: v1
kind: PersistentVolume
metadata:
  name: local-storage-pv-4
  namespace: elasticsearch
  labels:
    name: local-storage-pv-4
spec:
  capacity:
    storage: 1Gi
  accessModes:
  - ReadWriteonce
  persistentVolumeReclaimPolicy: Retain
  storageClassName: local-storage
  local:
    path: /data/es
  nodeAffinity:
    required:
      nodeSelectorTerms:
      - matchexpressions:
        - key: kubernetes.io/hostname
          operator: In
          values:
          - node1
---
apiVersion: v1
kind: PersistentVolume
metadata:
  name: local-storage-pv-5
  namespace: elasticsearch
  labels:
    name: local-storage-pv-5
spec:
  capacity:
    storage: 1Gi
  accessModes:
  - ReadWriteonce
  persistentVolumeReclaimPolicy: Retain
  storageClassName: local-storage
  local:
    path: /data/es
  nodeAffinity:
    required:
      nodeSelectorTerms:
      - matchexpressions:
        - key: kubernetes.io/hostname
          operator: In
          values:
          - node2

一共是5个PV，每个都通过nodeSelectorTerms跟k8s节点绑定。
执行一下：

kubectl apply -f pv.yaml

3、创建StatefulSet，ES属于数据库类型的应用，此类应用适合StatefulSet类型

[root@master1 tmp]# cat sts.yaml 
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: es7-cluster
  namespace: elasticsearch
spec:
  serviceName: elasticsearch7
  replicas: 5
  selector:
    matchLabels:
      app: elasticsearch7
  template:
    metadata:
      labels:
        app: elasticsearch7
    spec:
      containers:
      - name: elasticsearch7
        image: elasticsearch:7.16.2
        resources:
            limits:
              cpu: 1000m
            requests:
              cpu: 100m
        ports:
        - containerPort: 9200
          name: rest
          protocol: TCP
        - containerPort: 9300
          name: inter-node
          protocol: TCP
        volumeMounts:
        - name: data
          mountPath: /usr/share/elasticsearch/data
        env:
          - name: cluster.name
            value: k8s-logs
          - name: node.name
            valueFrom:
              fieldRef:
                fieldPath: metadata.name
          - name: discovery.zen.minimum_master_nodes
            value: "2"
          - name: discovery.seed_hosts
            value: "es7-cluster-0.elasticsearch7,es7-cluster-1.elasticsearch7,es7-cluster-2.elasticsearch7"
          - name: cluster.initial_master_nodes
            value: "es7-cluster-0,es7-cluster-1,es7-cluster-2"
          - name: ES_JAVA_OPTS
            value: "-Xms1g -Xmx1g"
      initContainers:
      - name: fix-permissions
        image: busybox
        command: ["sh", "-c", "chown -R 1000:1000 /usr/share/elasticsearch/data"]
        securityContext:
          privileged: true
        volumeMounts:
        - name: data
          mountPath: /usr/share/elasticsearch/data
      - name: increase-vm-max-map
        image: busybox
        command: ["sysctl", "-w", "vm.max_map_count=262144"]
        securityContext:
          privileged: true
      - name: increase-fd-ulimit
        image: busybox
        command: ["sh", "-c", "ulimit -n 65536"]
  volumeClaimTemplates:
  - metadata:
      name: data
    spec:
      accessModes: [ "ReadWriteOnce" ]
      storageClassName: "local-storage"
      resources:
        requests:
          storage: 1Gi

该ES集群通过volumeClaimTemplates来关联storageClass，并自动绑定相应的PV。
执行一下：

kubectl apply -f sts.yaml

4、创建NodePort类型的Service来蒋ES集群暴漏出去

[root@master1 tmp]# cat svc.yaml 
apiVersion: v1
kind: Service
metadata:
  name: elasticsearch7
  namespace: elasticsearch
spec:
  selector:
    app: elasticsearch7
  type: NodePort
  ports:
  - port: 9200
    nodePort: 30002
    targetPort: 9200

执行一下：

kubectl apply -f svc.yaml

以上就创建完了，我们来看一下上面创建的资源状态：
（1）storageclass

[root@master1 tmp]# kubectl get sc
NAME            PROVISIonER                    RECLAIMPOLICY   VOLUMEBINDINGMODE      ALLOWVOLUMEEXPANSION   AGE
local-storage   kubernetes.io/no-provisioner   Delete          WaitForFirstConsumer   false                  21h

（2）PV

[root@master1 tmp]# kubectl get pv
NAME                 CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS   CLAIM                              STORAGECLASS    REASON   AGE
local-storage-pv-1   1Gi        RWO            Retain           Bound    elasticsearch/data-es7-cluster-1   local-storage            21h
local-storage-pv-2   1Gi        RWO            Retain           Bound    elasticsearch/data-es7-cluster-2   local-storage            21h
local-storage-pv-3   1Gi        RWO            Retain           Bound    elasticsearch/data-es7-cluster-0   local-storage            21h
local-storage-pv-4   1Gi        RWO            Retain           Bound    elasticsearch/data-es7-cluster-4   local-storage            19m
local-storage-pv-5   1Gi        RWO            Retain           Bound    elasticsearch/data-es7-cluster-3   local-storage            19m

[root@master1 tmp]# kubectl get pvc -n elasticsearch
NAME                 STATUS   VOLUME               CAPACITY   ACCESS MODES   STORAGECLASS    AGE
data-es7-cluster-0   Bound    local-storage-pv-3   1Gi        RWO            local-storage   21h
data-es7-cluster-1   Bound    local-storage-pv-1   1Gi        RWO            local-storage   21h
data-es7-cluster-2   Bound    local-storage-pv-2   1Gi        RWO            local-storage   21h
data-es7-cluster-3   Bound    local-storage-pv-5   1Gi        RWO            local-storage   20m
data-es7-cluster-4   Bound    local-storage-pv-4   1Gi        RWO            local-storage   19m

（3）StatefulSet

[root@master1 tmp]# kubectl get statefulset -n elasticsearch
NAME          READY   AGE
es7-cluster   5/5     21h
[root@master1 tmp]# kubectl get pod -n elasticsearch
NAME            READY   STATUS    RESTARTS   AGE
es7-cluster-0   1/1     Running   1          21h
es7-cluster-1   1/1     Running   1          21h
es7-cluster-2   1/1     Running   1          21h
es7-cluster-3   1/1     Running   0          19m
es7-cluster-4   1/1     Running   0          18m

（4）Service

[root@master1 tmp]# kubectl get svc -n elasticsearch
NAME             TYPE       CLUSTER-IP      EXTERNAL-IP   PORT(S)          AGE
elasticsearch7   NodePort   10.97.196.176           9200:30002/TCP   21h

（5）通过restful接口查看ES集群状态

[root@master1 tmp]# curl 192.168.1.3:30002/_cat/nodes?v
ip             heap.percent ram.percent cpu load_1m load_5m load_15m node.role   master name
10.244.136.5             60          39   1    0.19    0.31     0.36 cdfhilmrstw -      es7-cluster-0
10.244.104.1             45          41   1    0.98    0.44     0.25 cdfhilmrstw -      es7-cluster-3
10.244.180.5             40          40   1    0.28    0.32     0.32 cdfhilmrstw -      es7-cluster-2
10.244.166.141           63          41   1    0.06    0.14     0.14 cdfhilmrstw -      es7-cluster-4
10.244.137.68            44          41   1    0.29    0.45     0.59 cdfhilmrstw *      es7-cluster-1

通过网页访问也是正常的：