WordPress + MySQL deployed in Kubernetes - MySQL Connection Error - mysql

Question

A Kubernetes scenario with Wordpress + Mysql in a local environment.
Wordpress Pod is unable to connect to Mysql database with the following error from Wordpress Pod logs:
MySQL Connection Error: (1045) Access denied for user 'root'#'10.44.0.5' (using password: YES)
Warning: mysqli::mysqli(): (HY000/1045): Access denied for user 'root'#'10.44.0.5' (using password: YES) in - on line 22
Instruction taken from kubernetes.io at link. The only change i made was creating a Secret resource to store password and to be pointed from Mysql and Wordpress containers.
apiVersion: v1
kind: Secret
metadata:
name: mysql-pass
namespace: default
data:
password: cGFzc3dvcmQxMjMK --> that is base64 of password123
type: Opaque
Pods are in default namespace both on node1 that is a worker node:
NAME READY STATUS RESTARTS AGE IP NODE
wordpress-554dfbbc47-hnr4n 0/1 Error 1 66s 10.44.0.5 node1
wordpress-mysql-5477cbdfbf-29w2r 1/1 Running 0 74s 10.44.0.4 node1
i've no skills about mysql but if i get bash shall in Mysql container and execute:
# mysql -u root -p
Enter password:
ERROR 1045 (28000): Access denied for user 'root'#'localhost' (using password: YES)
Here the Service output:
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S)
wordpress LoadBalancer 10.107.114.255 192.168.1.83 80:32336/TCP
wordpress-mysql ClusterIP None <none> 3306/TCP
Some env variables from MySql Pod:
....
HOSTNAME=wordpress-mysql-5477cbdfbf-29w2r
MYSQL_MAJOR=5.6
MYSQL_ROOT_PASSWORD=password123
MYSQL_VERSION=5.6.50-1debian9
....
PersistentVolume are working fine.
Quite stucked going ahead with troubleshooting. Help would appreciated.

Answer 1

After testing different images for Mysql and Wordpress and reading useful links on hub.docker.com mysql & wordpress i got the web application stack working.
The configuration:
MySQL:
apiVersion: v1
kind: Service
metadata:
name: wordpress-mysql
labels:
app: wordpress
spec:
ports:
- port: 3306
selector:
app: wordpress
tier: mysql
clusterIP: None
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: mysql-pv-claim
labels:
app: wordpress
spec:
accessModes:
- ReadWriteOnce
storageClassName: local-storage
resources:
requests:
storage: 1Gi
apiVersion: apps/v1
kind: Deployment
metadata:
name: wordpress-mysql
labels:
app: wordpress
spec:
selector:
matchLabels:
app: wordpress
tier: mysql
replicas: 1
strategy:
type: Recreate
template:
metadata:
labels:
app: wordpress
tier: mysql
spec:
containers:
- image: mysql:5.7
imagePullPolicy: IfNotPresent
name: mysql
env:
- name: MYSQL_ROOT_PASSWORD
valueFrom:
secretKeyRef:
name: root-pass
key: password
- name: MYSQL_DATABASE
value: mysql
- name: MYSQL_USER
value: mysql
- name: MYSQL_PASSWORD
valueFrom:
secretKeyRef:
name: mysql-pass
key: password
ports:
- containerPort: 3306
name: mysql
volumeMounts:
- name: mysql-persistent-storage
mountPath: /var/lib/mysql
nodeSelector:
storage: local
volumes:
- name: mysql-persistent-storage
persistentVolumeClaim:
claimName: mysql-pv-claim
Wordpress:
apiVersion: v1
kind: Service
metadata:
name: wordpress
labels:
app: wordpress
spec:
ports:
- port: 80
selector:
app: wordpress
tier: frontend
type: LoadBalancer
externalIPs:
- 192.168.1.83
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: wp-pv-claim
labels:
app: wordpress
spec:
accessModes:
- ReadWriteOnce
storageClassName: local-storage
resources:
requests:
storage: 1Gi
apiVersion: apps/v1
kind: Deployment
metadata:
name: wordpress
labels:
app: wordpress
spec:
selector:
matchLabels:
app: wordpress
tier: frontend
replicas: 1
strategy:
type: Recreate
template:
metadata:
labels:
app: wordpress
tier: frontend
spec:
containers:
- image: wordpress
name: wordpress
imagePullPolicy: IfNotPresent
env:
- name: WORDPRESS_DB_HOST
value: wordpress-mysql
- name: WORDPRESS_DB_PASSWORD
valueFrom:
secretKeyRef:
name: mysql-pass
key: password
- name: WORDPRESS_DB_USER
value: mysql
- name: WORDPRESS_DB_NAME
value: mysql
ports:
- containerPort: 80
name: wordpress
volumeMounts:
- name: wordpress-persistent-storage
mountPath: /var/www/html
nodeSelector:
storage: local
volumes:
- name: wordpress-persistent-storage
persistentVolumeClaim:
claimName: wp-pv-claim
Output PersitentVolume:
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS
mysql-pv-claim Bound persistent-volume-mysql 4Gi RWO local-storage
wp-pv-claim Bound persistent-volume-wordpress 2Gi RWO local-storage
Secrets:
apiVersion: v1
kind: Secret
metadata:
name: root-pass
namespace: default
data:
password: cGFzc3dvcmQ=
type: Opaque
apiVersion: v1
kind: Secret
metadata:
name: mysql-pass
namespace: default
data:
password: cGFzc3dvcmQ=
type: Opaque
Notes for my example configuration:
on node1 created directory /mysql/data & /wordpress/data (mount point for mysql and wordpress containers).
image used for mysql -> mysql:5.7
image used for wordpress -> wordpress
added environment variables according to the documentation of mysql and wordpress.

Answer 2

Did you apply your secret? is your secret available in kube env?