es-master.yml

apiVersion: apps/v1
kind: Deployment
metadata:
  namespace: default
  name: elasticsearch-master
  labels:
    component: elasticsearch
    role: master
spec:
  replicas: 3
  selector:
    matchLabels:
      app: elasticsearch
      role: master
  template:
    metadata:
      labels:
        app: elasticsearch
        role: master
    spec:
      affinity:
        # Try to put each ES master node on a different node in the K8s cluster
        podAntiAffinity:
          preferredDuringSchedulingIgnoredDuringExecution:
            - weight: 100
              podAffinityTerm:
                labelSelector:
                  matchExpressions:
                  - key: app
                    operator: In
                    values:
                      - elasticsearch
                  - key: role
                    operator: In
                    values:
                      - master
                topologyKey: kubernetes.io/hostname
      # spec.template.spec.initContainers
      initContainers:
        # Increase the default vm.max_map_count to 262144
        # https://www.elastic.co/guide/en/elasticsearch/reference/current/docker.html#docker-cli-run-prod-mode
        - name: increase-the-vm-max-map-count
          image: busybox
          command: ['sysctl', '-w', 'vm.max_map_count=262144']
          securityContext:
            privileged: true

      # spec.template.spec.containers
      containers:
        - name: elasticsearch
          image: docker.elastic.co/elasticsearch/elasticsearch:6.5.2
          ports:
            - containerPort: 9200
              name: http
            - containerPort: 9300
              name: transport
          livenessProbe:
            tcpSocket:
              port: transport
            initialDelaySeconds: 20
            periodSeconds: 10
          resources:
            requests:
              cpu: 0.25
            limits:
              cpu: 1
              memory: 1Gi

          # spec.template.spec.containers[elasticsearch].env
          env:
            - name: discovery.zen.ping.unicast.hosts
              value: "elasticsearch-master.default.svc.cluster.local,elasticsearch.default.svc.cluster.local"
            - name: ES_JAVA_OPTS
              value: -Xms512m -Xmx512m

            - name: discovery.zen.minimum_master_nodes
              value: "2"
            - name: node.master
              value: "true"
            - name: node.ingest
              value: "false"
            - name: node.data
              value: "false"
            - name: search.remote.connect
              value: "false"

            - name: cluster.name
              value: my-es-cluster
            - name: node.name
              valueFrom:
                fieldRef:
                  fieldPath: metadata.name

          # spec.template.spec.containers[elasticsearch].volumeMounts
          volumeMounts:
            - name: storage
              mountPath: /usr/share/elasticsearch/data
            - name: config
              # This path seems likely to break, but $JAVA_HOME doesn't work
              mountPath: /opt/jdk-11.0.1/lib/security/java.security
              subPath: java.security

      # spec.template.spec
      volumes:
        - name: config
          configMap:
            name: es-config
        - name: storage
          emptyDir:
            medium: ""
---
apiVersion: policy/v1beta1
kind: PodDisruptionBudget
metadata:
  namespace: default
  name: elasticsearch-master
spec:
  maxUnavailable: 1
  selector:
    matchLabels:
      app: elasticsearch
      role: master