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#
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# To create Elasticsearch frontend cluster Kubernetes service. 
# It sets up a load balancer on TCP port 9200 that distributes network traffic to the ES nodes.
apiVersion: v1
kind: Service
metadata:
  name: elasticsearch
  labels:
    component: elasticsearch
spec:
  selector:
    component: elasticsearch
  type: NodePort
  ports:
  - name: http
    port: 9200
    protocol: TCP
  - name: transport
    port: 9300
    protocol: TCP
---
# The Kubernetes deployment script for Elasticsearch replication nodes. It will create 1 node cluster.
# To scale the cluster as desired, you can create replicas of node use 'kubectl scale --replicas=3 rc es' command
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: es
  labels:
    component: elasticsearch
spec:
  replicas: 1
  template:
    metadata:
      labels:
        component: elasticsearch
      annotations:
        pod.beta.kubernetes.io/init-containers: '[
          {
          "name": "sysctl",
            "image": "busybox",
            "imagePullPolicy": "IfNotPresent",
            "command": ["sysctl", "-w", "vm.max_map_count=262144"],
            "securityContext": {
              "privileged": true
            }
          }
        ]'
    spec:
      containers:
      - name: es
        securityContext:
          capabilities:
            add:
# IPC_LOCK capability is enabled to allow Elasticsearch to lock the heap in memory so it will not be swapped.   
              - IPC_LOCK
# SYS_RESOURCE capability is set to control and override various resource limits.
              - SYS_RESOURCE
        image: quay.io/pires/docker-elasticsearch-kubernetes:5.2.2
        env:
        - name: "CLUSTER_NAME"
          value: "myesdb"
        - name: "DISCOVERY_SERVICE"
          value: "elasticsearch"
        - name: NODE_MASTER
          value: "true"
        - name: NODE_DATA
          value: "true"
        - name: HTTP_ENABLE
          value: "true"
        ports:
        - containerPort: 9200
          name: http
          protocol: TCP
        - containerPort: 9300
          name: transport
          protocol: TCP
        volumeMounts:
        - mountPath: /data
          name: storage
      volumes:
      - name: storage
        emptyDir: {}