How to persist data using a postgres database, Docker, and Kubernetes?

In the end, it seems that the real problem was the fact that I was trying to create the database from my entrypoint script. Things such as creating a db or a user should be done at container creation time so I ended up using the standard Postgres image, which actually provides a simple and easy way to create an user and a db.

This is the fully functional configuration file for Postgres.

apiVersion: v1kind: Podmetadata:  name: postgres  labels:    name: postgresspec:  containers:    - name: postgres      image: postgres      env:        - name: PGDATA          value: /var/lib/postgresql/data/pgdata        - name: POSTGRES_USER          value: myuser        - name: POSTGRES_PASSWORD          value: mypassword        - name: POSTGRES_DB          value: mydb      ports:        - containerPort: 5432      volumeMounts:        - mountPath: /var/lib/postgresql/data          name: pg-data  volumes:    - name: pg-data      persistentVolumeClaim:        claimName: pg-data-claim

Thanks to all those who helped me :)

• does your custom postgresql persist data at /var/lib/postgresql/data?
• are you able to get logs from your postgresql container and spot anything interesting?
• when your pod is running, can you see the mountpoints inside your container and check the persistent disk is there?

I followed this scenario and I was able to persist my data by changing the mountPath to /var/lib/postgresql and also reproduced using cassandra (i.e. /var/lib/cassandra for mountPath)

I was able to delete/restart pods from different nodes/hosts and still see my "users" table and the data I previously entered. However, I was not using a custom image, I just used standard docker images.