I have spent some time setting up my own instance of CloudnativePG inside my Kubernetes cluster. I have two instances a dev instance, and a "prod" instance. Normally I would use pg_dump to backup the databases, but I wanted to try something different.

Therefore I spun up my own instance of Minio and decided to use that as all backups, this includes CloudnativePG as well as applications such as Longhorn but this will be about setting up CloudnativePG.

Setting up backup to Minio Gateway

MinIO Gateway as a common interface which relays backup objects to other cloud storage solutions, like S3. Specifically, the CloudNativePG cluster can directly point to a local MinIO Gateway as an endpoint. If you read through the CNPG docs, you will be informed about creating a Minio service. For my setup, that isn't needed as I don't have Minio hosted in my Kubernetes cluster mine is hosted on a VM, which you can read about here

First step is to create a secret manifest as MinIO secrets will be used by both the PostgreSQL cluster and the MinIO instance. Therefore, you must create them in the same namespace below is how I created my secret and deployed it within the same directory as my cluster manifests.

apiVersion: v1
kind: Secret
metadata:
  name: cnpg-prod-minio
  namespace: cnpg-prod
type: Opaque
data:
  MINIO_ACCESS_KEY: <access-key>
  MINIO_SECRET_KEY: <secret-key>

Once you have your secret manifest created it is now time to add your backup config to your Cluster manifest. Below is how I have laid mine out.

apiVersion: postgresql.cnpg.io/v1
kind: Cluster
metadata:
  name: cnpg-prod
  namespace: cnpg-prod
spec:
  description: "Homelab Prod Cluster"
  ...

  backup:
    retentionPolicy: "10d"
    barmanObjectStore:
      destinationPath: s3://cnpg-backups/
      endpointURL: http://192.168.6.69:9000
      s3Credentials:
        accessKeyId:
          name: cnpg-prod-minio
          key: MINIO_ACCESS_KEY
        secretAccessKey:
          name: cnpg-prod-minio
          key: MINIO_SECRET_KEY

  ...

Once that has been added it's time to either set up a scheduled backup in a separate manifest like I have below:

apiVersion: postgresql.cnpg.io/v1
kind: ScheduledBackup
metadata:
  name: weekly-backup
spec:
  schedule: '@weekly'
  backupOwnerReference: self
  cluster:
    name: cnpg-prod

Or set up a on-demand backup as stated in the docs. Once the backup manifest has been created, the operator will create a backup to your Minio instance.

Now I have backups of my databases in object storage, instead of the drive that hosts the database.