Skip to main content
Version: 3.1

PostgreSQL on Portworx

Perform the steps in this topic to deploy PostgreSQL with Portworx on Kubernetes.

Prerequisites

Create a StorageClass

  1. Create a file named px-postgres-sc.yaml, and copy in the following spec:

    kind: StorageClass
    apiVersion: storage.k8s.io/v1
    metadata:
    name: px-postgres-sc
    provisioner: kubernetes.io/portworx-volume
    parameters:
    repl: "2"
    allowVolumeExpansion: true

    Note the following about this StorageClass:

    • The provisioner parameter is set to kubernetes.io/portworx-volume. For details about the Portworx-specific parameters, refer to the Portworx Volume section of the Kubernetes website.
    • Two replicas of each volume will be created
  2. Apply the spec by entering the following command:

    kubectl apply -f px-postgres-sc.yaml

Create a PVC

  1. Create a file named px-postgres-vol.yaml with the following content:

    kind: PersistentVolumeClaim
    apiVersion: v1
    metadata:
    name: postgres-data
    annotations:
    volume.beta.kubernetes.io/storage-class: px-postgres-sc
    spec:
    accessModes:
    - ReadWriteOnce
    resources:
    requests:
    storage: 1Gi

    Note that this PVC references the px-postgres-sc storage class defined in the Create a StorageClass section. As a result, Kubernetes will automatically create a new PVC for each replica.

  2. Apply the spec by entering the following command:

    kubectl apply -f px-postgres-vol.yaml

Deploy PostgreSQL using Stork

  1. Create a file named px-postgres-app.yaml with the following content:

    apiVersion: apps/v1
    kind: Deployment
    metadata:
    name: postgres
    spec:
    selector:
    matchLabels:
    app: postgres
    strategy:
    rollingUpdate:
    maxSurge: 1
    maxUnavailable: 1
    type: RollingUpdate
    replicas: 1
    template:
    metadata:
    labels:
    app: postgres
    spec:
    schedulerName: stork
    affinity:
    nodeAffinity:
    requiredDuringSchedulingIgnoredDuringExecution:
    nodeSelectorTerms:
    - matchExpressions:
    - key: px/enabled
    operator: NotIn
    values:
    - "false"
    containers:
    - name: postgres
    image: postgres:9.5
    imagePullPolicy: "IfNotPresent"
    ports:
    - containerPort: 5432
    env:
    - name: POSTGRES_USER
    value: pgbench
    - name: POSTGRES_PASSWORD
    value: superpostgres
    - name: PGBENCH_PASSWORD
    value: superpostgres
    - name: PGDATA
    value: /var/lib/postgresql/data/pgdata
    volumeMounts:
    - mountPath: /var/lib/postgresql/data
    name: postgredb
    volumes:
    - name: postgredb
    persistentVolumeClaim:
    claimName: postgres-data

    Note the following:

    • Specifies Stork as scheduler (schedulerName: stork)
    • Sets the following environment variables:
      • POSTGRES_USER (defines the superuser)
      • POSTGRES_PASSWORD (specifies the superuser password)
      • PGDATA (configures the location for the database files)
    • References the postgres-data PVC defined in the Create a PVC section.
  1. Apply the spec by entering the following command:

    kubectl apply -f px-postgres-app.yaml

Verify your PostgreSQL installation

  1. Enter the following kubectl get command to list your storage classes:

    kubectl get sc
    NAME             PROVISIONER                     AGE
    px-postgres-sc kubernetes.io/portworx-volume 1h

    In the above example output, note that the provisioner is set to kubernetes.io/portworx-volume

  1. Enter the kubectl get pvc command to verify that the PVC is bound to a volume:

    kubectl get pvc
    NAME            STATUS    VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS     AGE
    postgres-data Bound pvc-60e43292-06e3-11e8-96b4-022185d04910 1Gi RWO px-postgres-sc 1h
  2. Use the kubectl get pods command to verify the status of the PostgreSQL pod:

    kubectl get pod
    NAME                        READY     STATUS    RESTARTS   AGE
    postgres-86cb8587c4-l9r48 1/1 Running 0 1h

    Make a note of the name of the pod. You'll need it in the next step.

  3. Enter the following kubectl exec command, specifying your own pod name, to open a shell session into your pod. This example opens the postgres-86cb8587c4-l9r48 pod:

    kubectl exec -it postgres-86cb8587c4-l9r48 -- bash
    root@postgres-86cb8587c4-l9r48:/#
  4. Start the PostgreSQL interactive shell. Use the-U flag to connect as the pgbench user:

    root@postgres-86cb8587c4-l9r48:/# psql -U pgbench
    psql (9.5.10)
    Type "help" for help.
  5. List your databases:

    pgbench=# \l
                                  List of databases
    Name | Owner | Encoding | Collate | Ctype | Access privileges
    -----------+---------+----------+------------+------------+---------------------
    pgbench | pgbench | UTF8 | en_US.utf8 | en_US.utf8 |
    postgres | pgbench | UTF8 | en_US.utf8 | en_US.utf8 |
    template0 | pgbench | UTF8 | en_US.utf8 | en_US.utf8 | =c/pgbench +
    | | | | | pgbench=CTc/pgbench
    template1 | pgbench | UTF8 | en_US.utf8 | en_US.utf8 | =c/pgbench +
    | | | | | pgbench=CTc/pgbench
    (4 rows)
  6. Exit the PostgreSQL interactive shell:

    pgbench=# \q

Discussion Forum

If you have more questions about this application, please head over to our discussion forum and feel free to ask more questions.

Was this page helpful?