cassandra-statefulset.yml

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: cassandra
  labels:
    app: cassandra
  namespace: bikes-cluster-1
spec:
  serviceName: cassandra
  replicas: 3
  selector:
    matchLabels:
      app: cassandra
  template:
    metadata:
      labels:
        app: cassandra
        namespace: bikes-cluster-1
    spec:
      terminationGracePeriodSeconds: 1800
      containers:
        - name: cassandra
          image: cassandra:3.11.14
          imagePullPolicy: IfNotPresent
          ports:
            - containerPort: 7000
              name: intra-node
            - containerPort: 7001
              name: tls-intra-node
            - containerPort: 7199
              name: jmx
            - containerPort: 9042
              name: cql
          resources:
            limits:
              cpu: "500m"
              memory: 1Gi
            requests:
              cpu: "500m"
              memory: 1Gi
          securityContext:
            capabilities:
              add:
                - IPC_LOCK
          lifecycle:
            preStop:
              exec:
                command:
                  - /bin/sh
                  - -c
                  - nodetool drain
          env:
            - name: NAMESPACE
              valueFrom:
                fieldRef:
                  fieldPath: metadata.namespace
            - name: MAX_HEAP_SIZE
              value: 512M
            - name: HEAP_NEWSIZE
              value: 100M
            - name: CASSANDRA_SEEDS
              value: "cassandra-0.cassandra.$(NAMESPACE).svc.cluster.local"
            - name: CASSANDRA_CLUSTER_NAME
              value: "K8Demo"
            - name: CASSANDRA_DC
              value: "datacenter1"
            - name: CASSANDRA_RACK
              value: "Rack1-K8Demo"
            - name: POD_IP
              valueFrom:
                fieldRef:
                  fieldPath: status.podIP
          readinessProbe:
            exec:
              command:
                - /bin/bash
                - -c
                # We could use `nodetool` in the next probing command like this:
                # if [[ $(nodetool status | grep $POD_IP) == *"UN"* ]]; then exit 0; else exit 1; fi
                # but then Kubernetes will issue OOMKilled for not-so-clear-yet reasons.
                # Command `nodetool` can be used, but then `initialDelaySeconds`, `timeoutSeconds` and `periodSeconds`
                # should be set carefully and accordingly.
                # See https://blog.colinbreck.com/kubernetes-liveness-and-readiness-probes-how-to-avoid-shooting-yourself-in-the-foot/
                # Another ready probe command, using `cqlsh`, which is faster than `nodetool`, could be:
                # cqlsh -e 'SELECT schema_version, release_version FROM  system.local'
                # Again, params `initialDelaySeconds`, `timeoutSeconds` and `periodSeconds` should be chosen wisely.
                - echo "/ready-probe.sh :-)"
            initialDelaySeconds: 15
            timeoutSeconds: 25
            periodSeconds: 30
          # These volume mounts are persistent. They are like inline claims,
          # but not exactly because the names need to match exactly one of
          # the stateful pod volumes.
          volumeMounts:
            - name: cassandra-data
              mountPath: /cassandra_data
  # These are converted to volume claims by the controller
  # and mounted at the paths mentioned above.
  # do not use these in production until ssd GCEPersistentDisk or other ssd pd
  volumeClaimTemplates:
    - metadata:
        name: cassandra-data
        namespace: bikes-cluster-1
      spec:
        accessModes: [ "ReadWriteOnce" ]
        storageClassName: local-path
        resources:
          requests:
            storage: 1Gi