Kubernetes: Cassandra(stateful set) deployment on GCP

10/30/2018

Has anyone tried deploying Cassandra (POC) on GCP using kubernetes (not GKE). If so can you please share info on how to get it working?

-- user3435964
cassandra
kubernetes
kubernetes-statefulset

2 Answers

10/30/2018

You could start by looking at IBM's Scalable-Cassandra-deployment-on-Kubernetes.

For seeds discovery you can use a headless service, similar to this Multi-node Cassandra Cluster Made Easy with Kubernetes.

Some difficulties:

You could also check the Cassandra mailing list, since there are people there already using Cassandra over K8s in production.

-- Horia
Source: StackOverflow

10/30/2018

I have implemented cassandra on kubernetes. Please find my deployment and service yaml files:

apiVersion: v1
kind: Service
metadata:
  labels:
    app: cassandra
  name: cassandra
spec:
  clusterIP: None
  ports:
  - port: 9042
  selector:
    app: cassandra
---
apiVersion: apps/v1beta2
kind: StatefulSet
metadata:
  name: cassandra
  labels:
    app: cassandra
spec:
  serviceName: cassandra
  replicas: 3
  updateStrategy:
    type: RollingUpdate
  selector:
    matchLabels:
      app: cassandra
  template:
    metadata:
      labels:
        app: cassandra
    spec:
      terminationGracePeriodSeconds: 1800
      containers:
      - name: cassandra
        image: gcr.io/google-samples/cassandra:v12
        imagePullPolicy: Always
        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: MAX_HEAP_SIZE
            value: 512M
          - name: HEAP_NEWSIZE
            value: 100M
          - name: CASSANDRA_SEEDS
            value: "cassandra-0.cassandra.default.svc.cluster.local"
          - name: CASSANDRA_CLUSTER_NAME
            value: "K8Demo"
          - name: CASSANDRA_DC
            value: "DC1-K8Demo"
          - name: CASSANDRA_RACK
            value: "Rack1-K8Demo"
          - name: POD_IP
            valueFrom:
              fieldRef:
                fieldPath: status.podIP
        readinessProbe:
          exec:
            command:
            - /bin/bash
            - -c
            - /ready-probe.sh
          initialDelaySeconds: 15
          timeoutSeconds: 5
        volumeMounts:
        - name: cassandra-data
          mountPath: /cassandra_data
  volumeClaimTemplates:
  - metadata:
      name: cassandra-data
    spec:
      accessModes: [ "ReadWriteOnce" ]
      storageClassName: "fast"
      resources:
        requests:
          storage: 5Gi    

Hope this helps.

-- Prafull Ladha
Source: StackOverflow