最近在折腾K8S下安装ES，ECK很是方便，但是也屏蔽了不少细节，还是希望多从其他方式怼怼，记录一次使用LocalPV安装ES的过程。

环境

• Kubernetes 1.18.2 集群 - 2节点：1master + 1node
  推荐使用一下Kuboard的教程：
  https://kuboard.cn/install/install-k8s.html
• ES 7.6.2版本

关于LocalPV

• 只需要在volumeClaimTemplates中注明storageClassName，采用 kubernetes.io/no-provisioner的方式，根据匹配的名称就会自动的去申请可用的PV

准备

• node节点的hostname为zqw02
• 登陆zqw02，创建本地卷

mkdir -p /mnt/localpv/es7-0 /mnt/localpv/es7-1 /mnt/localpv/es7-2

• 目录授权

chmod -R 777 /mnt/localpv/

创建ES集群的命名空间

• ns.yaml

[root@zqw01 es1]# cat ns.yaml
apiVersion: v1
kind: Namespace
metadata:
  name: logging

• 执行文件

kubectl create -f ns.yml

创建storage provisioner

• stc.yaml

[root@zqw01 es1]# cat stc.yaml
kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
  namespace: logging
  name: local-storage
provisioner: kubernetes.io/no-provisioner
volumeBindingMode: WaitForFirstConsumer

• 执行文件

kubectl create -f stc.yaml

创建PV资源池（可以满足需求个数）

• 创建PV资源文件

[root@zqw01 es1]# cat lp0.yaml lp1.yaml lp2.yaml
apiVersion: v1
kind: PersistentVolume
metadata:
  name: local-storage-pv-0
  labels:
    name: local-storage-pv-0
spec:
  capacity:
    storage: 20Gi
  accessModes:
  - ReadWriteOnce
  persistentVolumeReclaimPolicy: Retain
  storageClassName: local-storage
  local:
    path: /mnt/localpv/es7-0
  nodeAffinity:
    required:
      nodeSelectorTerms:
      - matchExpressions:
        - key: kubernetes.io/hostname
          operator: In
          values:
          - zqw02
---
apiVersion: v1
kind: PersistentVolume
metadata:
  name: local-storage-pv-1
  labels:
    name: local-storage-pv-1
spec:
  capacity:
    storage: 20Gi
  accessModes:
  - ReadWriteOnce
  persistentVolumeReclaimPolicy: Retain
  storageClassName: local-storage
  local:
    path: /mnt/localpv/es7-1
  nodeAffinity:
    required:
      nodeSelectorTerms:
      - matchExpressions:
        - key: kubernetes.io/hostname
          operator: In
          values:
          - zqw02
---
apiVersion: v1
kind: PersistentVolume
metadata:
  name: local-storage-pv-2
  labels:
    name: local-storage-pv-2
spec:
  capacity:
    storage: 20Gi
  accessModes:
  - ReadWriteOnce
  persistentVolumeReclaimPolicy: Retain
  storageClassName: local-storage
  local:
    path: /mnt/localpv/es7-2
  nodeAffinity:
    required:
      nodeSelectorTerms:
      - matchExpressions:
        - key: kubernetes.io/hostname
          operator: In
          values:
          - zqw02

• 执行PV资源文件

kubectl create -f lp0.yml
kubectl create -f lp1.yml
kubectl create -f lp2.yml

创建ES集群Service

[root@zqw01 es1]# cat svc.yaml
kind: Service
apiVersion: v1
metadata:
  name: elasticsearch7
  namespace: logging
  labels:
    app: elasticsearch7
spec:
  selector:
    app: elasticsearch7
  type: NodePort
  ports:
    - port: 9200
      name: rest
      nodePort: 32000
    - port: 9300
      name: inter-node

• 执行文件

kubectl create -f svc.yaml

创建ES StatefulSet

[root@zqw01 es1]# cat sts.yaml
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: es7-cluster
  namespace: logging
spec:
  serviceName: elasticsearch7
  replicas: 3
  selector:
    matchLabels:
      app: elasticsearch7
  template:
    metadata:
      labels:
        app: elasticsearch7
    spec:
      containers:
      - name: elasticsearch7
        image: elasticsearch:7.6.2
        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.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: 20Gi

• 执行文件

kubectl create -f  sts.yaml

检验

• 查看Service

[root@zqw01 es1]# kubectl get svc -n logging
NAME             TYPE       CLUSTER-IP     EXTERNAL-IP   PORT(S)                         AGE
elasticsearch7   NodePort   10.96.55.170   <none>        9200:32000/TCP,9300:31147/TCP   41m

• 集群状态

[root@zqw01 es1]# curl 10.96.55.170:9200
{
  "name" : "es7-cluster-1",
  "cluster_name" : "k8s-logs",
  "cluster_uuid" : "R-OGPazVTBaemL0M6jRJ1g",
  "version" : {
    "number" : "7.6.2",
    "build_flavor" : "default",
    "build_type" : "docker",
    "build_hash" : "ef48eb35cf30adf4db14086e8aabd07ef6fb113f",
    "build_date" : "2020-03-26T06:34:37.794943Z",
    "build_snapshot" : false,
    "lucene_version" : "8.4.0",
    "minimum_wire_compatibility_version" : "6.8.0",
    "minimum_index_compatibility_version" : "6.0.0-beta1"
  },
  "tagline" : "You Know, for Search"
}

• 查看PVC/PV的情况

[root@zqw01 es1]# kubectl get pv
NAME                 CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS   CLAIM                        STORAGECLASS    REASON   AGE
local-storage-pv-0   20Gi       RWO            Retain           Bound    logging/data-es7-cluster-1   local-storage            47m
local-storage-pv-1   20Gi       RWO            Retain           Bound    logging/data-es7-cluster-0   local-storage            47m
local-storage-pv-2   20Gi       RWO            Retain           Bound    logging/data-es7-cluster-2   local-storage            47m
[root@zqw01 es1]#
[root@zqw01 es1]# kubectl get pvc -n logging
NAME                 STATUS   VOLUME               CAPACITY   ACCESS MODES   STORAGECLASS    AGE
data-es7-cluster-0   Bound    local-storage-pv-1   20Gi       RWO            local-storage   42m
data-es7-cluster-1   Bound    local-storage-pv-0   20Gi       RWO            local-storage   41m
data-es7-cluster-2   Bound    local-storage-pv-2   20Gi       RWO            local-storage   40m

可以看到PV-PVC的对应关系还是有一定的随机选择性，当然node是固定的了

参考

https://hacpai.com/article/1586757433779