MySQL Kubernetes

Question

I have such a mysql configuration for kubernetes. But I can not connect to database with my local mysql. I am doing port-forward: kubectl port-forward svc/mysql 3307 and then try to connect with command: mysql -h 127.0.0.1 -P 3307 -uroot -p

with password: pass

This password is defined in secret file for the root user. The error is: ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: YES)

Do you have idea what could be wrong?

mysql-deployment:

apiVersion: v1
kind: Service
metadata:
  name: mysql 
  labels:
    app: mysql
    tier: database
spec:
  ports:
    - port: 3307
      targetPort: 3306
  selector:       
    app: mysql
    tier: database
---

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: mysql-pv-claim 
  labels:
    app: mysql
    tier: database
spec:
  accessModes:
    - ReadWriteOnce   
  resources:
    requests:
      storage: 1Gi   
---
# 
apiVersion: apps/v1
kind: Deployment
metadata:
  name: mysql
  labels:
    app: mysql
    tier: database
spec:
  selector:
    matchLabels:
      app: mysql
      tier: database
  strategy:
    type: Recreate
  template:
    metadata:
      labels: 
        app: mysql
        tier: database
    spec:
      containers:
        - image: mysql:5.7 # image from docker-hub
          args:
            - "--ignore-db-dir=lost+found" 
          name: mysql
          env:
            - name: MYSQL_ROOT_PASSWORD 
              valueFrom:
                secretKeyRef:
                  name: db-root-credentials 
                  key: password  
            - name: MYSQL_USER 
              valueFrom:
                secretKeyRef:
                  name: db-credentials
                  key: username
            - name: MYSQL_PASSWORD 
              valueFrom:
                secretKeyRef:
                  name: db-credentials
                  key: password
            - name: MYSQL_DATABASE 
              valueFrom:
                configMapKeyRef:
                  name: db-conf
                  key: name
          ports:
            - containerPort: 3306
              name: mysql
          volumeMounts:        
            - name: mysql-persistent-storage
              mountPath: 
      volumes:
        - name: mysql-persistent-storage 
          persistentVolumeClaim:
            claimName: mysql-pv-claim

mysqldb-root-credentials:

apiVersion: v1
kind: Secret
metadata:
  name: db-root-credentials
data:
  password: cGFzcwo=

mysqldb-credentials:

apiVersion: v1
kind: Secret
metadata:
  name: db-credentials
data:
  username: c2ViYQo=
  password: c2ViYQo=

Answer 1

I've reproduced your issue and solve it by changing the way secrets are created. I used kubectl CLI to create secrets:

kubectl create secret generic db-credentials --from-literal=password=xyz --from-literal=username=xyz
kubectl create secret generic mysql-pass --from-literal=password=pass

Then deployed PVC, Deployment and Service :

apiVersion: v1
kind: Service
metadata:
  name: mysql 
  labels:
    app: mysql
    tier: database
spec:
  ports:
    - port: 3306
      targetPort: 3306
  selector:       
    app: mysql
    tier: database
---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: mysql-pv-claim 
  labels:
    app: mysql
    tier: database
spec:
  accessModes:
    - ReadWriteOnce   
  resources:
    requests:
      storage: 1Gi   
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: mysql
  labels:
    app: mysql
    tier: database
spec:
  selector:
    matchLabels:
      app: mysql
      tier: database
  strategy:
    type: Recreate
  template:
    metadata:
      labels: 
        app: mysql
        tier: database
    spec:
      containers:
        - image: mysql:5.7 # image from docker-hub
          args:
            - "--ignore-db-dir=lost+found" 
          name: mysql
          env:
            - name: MYSQL_ROOT_PASSWORD 
              valueFrom:
                secretKeyRef:
                  name: mysql-pass
                  key: password  
            - name: MYSQL_USER 
              valueFrom:
                secretKeyRef:
                  name: db-credentials
                  key: username
            - name: MYSQL_PASSWORD 
              valueFrom:
                secretKeyRef:
                  name: db-credentials
                  key: password
          ports:
            - containerPort: 3306
              name: mysql
          volumeMounts:        
            - name: mysql-persistent-storage
              mountPath: /var/lib/mysql
      volumes:
        - name: mysql-persistent-storage 
          persistentVolumeClaim:
            claimName: mysql-pv-claim

Exec to pod:

kubectl exec -it mysql-78d9b7b765-2ms5n -- mysql -h 127.0.0.1 -P 3306 -uroot -p

Once I enter the root password everything works fine:

Welcome to the MySQL monitor.  Commands end with ; or \g.
[...]

mysql>