How to get into postgres in Kubernetes with local dev minikube

Question

Can please somebody help me? This is my first post here, and I am really exited to start posting here and helping people but I need help first.

I am deploying my own Postgres database on Minikube. For db, password and username I am using secrets.

Data is encoded with base64

1. POSTGRES_USER = website_user
2. POSTGRES_DB = website
3. POSTGRES_PASSWORD = pass

I also exec into container to see if I could see these envs and they were there.

The problem is when I try to enter into postgres with psql. I checked minikube ip and typed correct password(pass) after this command:

pqsl -h 192.168.99.100 -U website_user -p 31315 website

Error

Password for user website_user:
psql: FATAL: password authentication failed for user "website_user"

Also if I exec into my pod:

kubectl exec -it postgres-deployment-744fcdd5f5-7f7vx bash

And try to enter into postgres I get:

psql -h $(hostname -i) -U website_user -p 5432 website

Error:

Password for user website_user:
psql: FATAL: password authentication failed for user "website_user"

I am lacking something here.I tried also ps aux in container, and everything seems to be find postgres processes are running

kubectl get all

Output:

NAME                                       READY   STATUS    RESTARTS   AGE
pod/postgres-deployment-744fcdd5f5-7f7vx   1/1     Running   0          18m

NAME                       TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)          AGE
service/kubernetes         ClusterIP   10.96.0.1        <none>        443/TCP          19m
service/postgres-service   NodePort    10.109.235.114   <none>        5432:31315/TCP   18m

NAME                                  READY   UP-TO-DATE   AVAILABLE   AGE
deployment.apps/postgres-deployment   1/1     1            1           18m

NAME                                             DESIRED   CURRENT   READY   AGE
replicaset.apps/postgres-deployment-744fcdd5f5   1         1         1       18m

# Secret store
apiVersion: v1
kind: Secret
metadata:
  name: postgres-credentials
type: Opaque
data:
  POSTGRES_USER: d2Vic2l0ZV91c2VyCg==
  POSTGRES_PASSWORD: cGFzcwo=
  POSTGRES_DB: d2Vic2l0ZQo=


---
# Persistent Volume
apiVersion: v1
kind: PersistentVolume
metadata:
  name: postgres-pv
  labels:
    type: local
spec:
  storageClassName: manual
  capacity:
    storage: 2Gi
  accessModes:
    - ReadWriteOnce
  hostPath:
    path: /data/postgres-pv


---
# Persistent Volume Claim
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: postgres-pvc
  labels:
    type: local
spec:
  storageClassName: manual
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 2Gi
  volumeName: postgres-pv

---
# Deployment
apiVersion: apps/v1
kind: Deployment
metadata:
  name: postgres-deployment
spec:
  selector:
    matchLabels:
      app: postgres-container
  template:
    metadata:
      labels:
        app: postgres-container
    spec:
      containers:
        - name: postgres-container
          image: postgres:9.6.6
          env:
            - name: POSTGRES_USER
              valueFrom:
                secretKeyRef:
                  name: postgres-credentials
                  key: POSTGRES_USER

            - name: POSTGRES_DB
              valueFrom:
                secretKeyRef:
                  name: postgres-credentials
                  key: POSTGRES_DB

            - name: POSTGRES_PASSWORD
              valueFrom:
                secretKeyRef:
                  name: postgres-credentials
                  key: POSTGRES_PASSWORD

          ports:
            - containerPort: 5432
          volumeMounts:
            - mountPath: /var/lib/postgresql/data
              name: postgres-volume-mount
      volumes:
        - name: postgres-volume-mount
          persistentVolumeClaim:
            claimName: postgres-pvc

---
apiVersion: v1
kind: Service
metadata:
  name: postgres-service
spec:
  selector:
    app: postgres-container
  ports:
    - port: 5432
      protocol: TCP
      targetPort: 5432
  type: NodePort

Answer 1

You created all your values with:

• $ echo "value" | base64
• which instead you should use: $ echo -n "value" | base64

Following official man page of echo:

Description

Echo the STRING(s) to standard output.

-n = do not output the trailing newline

TL;DR: You need to edit your Secret definition with new values:

• $ echo -n "website_user" | base64
• $ echo -n "website" | base64
• $ echo -n "pass" | base64

---

You created your Secret with a trailing newline. Please take a look at below example:

• POSTGRES_USER:
  • $ echo "website_user" | base64
    • output: d2Vic2l0ZV91c2VyCg== which is the same as yours
  • $ echo -n "website_user" | base64
    • output: d2Vic2l0ZV91c2Vy which is the correct value
• POSTGRES_PASSWORD:
  • $ echo "pass" | base64
    • output: cGFzcwo= which is the same as yours
  • $ echo -n "pass" | base64
    • output: cGFzcw== which is the correct value
• POSTGRES_DB:
  • $ echo "website" | base64
    • output: d2Vic2l0ZQo= which is the same as yours
  • $ echo -n "website" | base64
    • output: d2Vic2l0ZQ== which is the correct value

Your Secret should look like that:

apiVersion: v1
kind: Secret
metadata:
  name: postgres-credentials
type: Opaque
data:
  POSTGRES_USER: d2Vic2l0ZV91c2Vy
  POSTGRES_PASSWORD: cGFzcw==
  POSTGRES_DB: d2Vic2l0ZQ==

If you create it with a new Secret you should be able to connect to the database:

root@postgres-deployment-64d697868c-njl7q:/# psql -h $(hostname -i) -U website_user -p 5432 website
Password for user website_user: 
psql (9.6.6)
Type "help" for help.

website=# 

Please take a look on additional links:

• Github.com: Kubernetes: issues: Config map vs secret to store credentials for Postgres deployment
• Kubernetes.io: Secrets