Storage Configuration on K8S

MD Core containers are stateless and don't require any persistent storage by default. However, there are some cases where it is needed to attach a volume to the app container or database container.

Configure Database Storage

If the PostgreSQL database is deployed in the cluster, then it's recommended to use persistent storage managed by a cloud provider.

When using an external database that is not deployed from the MD Core chart, the deploy_with_core_db value has to be set to false in order to not deploy an additional database from the chart.

The helm chart can be configured to use a custom storage class or persistent volume by setting the storage_provisioner value to custom.

Available storage providers:

• hostPath: doesn't use any PVCs in the pod definitions and just mounts a path on the host starting with the hostPathPrefix
• custom: mounts from the PVC named as the storage_name value and uses component name as the subpath

Adding the Kubernetes yaml for the persistent volume claim in the storage_configs value and then using the pvc name in the storage_name value to tell the container where to mount to volume. Here's an example using managed storage in Azure:

storage_configs:          # Example using a PVC with dynamic provisioning from an existing storage class

  pvc-example:

    apiVersion: v1

    kind: PersistentVolumeClaim

    metadata:

      name: md-core-store-data-pvc

    spec:

      accessModes:

        - ReadWriteOnce

      resources:

        requests:

          storage: 1Gi

      storageClassName: managed-premium

core_components:

  md-core:

    extraVolumeMounts:

      - name: md-core-store-data

        mountPath: /var/lib/ometascan

    extraVolumes:

      configStore:

        name: md-core-store-data

        persistentVolumeClaim:

          claimName: md-core-store-data-pvc