Here are the key components and steps involved in setting up a simple stateful PostgreSQL deployment on Kubernetes:
Create a Storage Class: Define a StorageClass resource in Kubernetes, specifying the type of storage to be used and the access mode (read-write, read-only, etc.).
Create a Persistent Volume Claim: Define a PersistentVolumeClaim (PVC) to request a specific amount of storage from the storage class for your PostgreSQL database.
Create a ConfigMap: Define a ConfigMap to store your database configuration settings (e.g., usernames, passwords, etc.), separate from your application code.
Create a Secret: Store sensitive data (e.g., database passwords) securely in a Secret object. The Secret will be mounted as a volume in the pod and the environment variables will be set.
Create a StatefulSet: Define a StatefulSet that manages the deployment of your PostgreSQL pods. Specify the container image, port, volumes (PVC and ConfigMap), and a startup script. It ensures the unique identifier for each pod and guarantees the order of pod creation/deletion.
Learn more from the following resources: