Access MySQL Single-Instance Kubernetes Deployment - mysql

Question

I was following the Run a Single-Instance Stateful Application tutorial of Kubernetes (I changed the MySQL docker image's tag to 8), and it seems the server is running correctly:
But when I try to connect the server as the tutorial suggesting:
kubectl run -it --rm --image=mysql:8 --restart=Never mysql-client -- mysql -h mysql -ppassword
I get the following error:
ERROR 1045 (28000): Access denied for user 'root'#'10.1.0.99' (using password: YES)
pod "mysql-client" deleted
I already looked at those questions:
Can't access mysql root or user after kubernetes deployment
Access MySQL Kubernetes Deployment in MySQL Workbench
But changing the mountPath or port didn't work.

Answer 1

Default behavior of root account can only be connected to from inside the container. Here's an updated version of the example that allows you to connect from remote:
apiVersion: apps/v1
kind: Deployment
metadata:
name: mysql
spec:
selector:
matchLabels:
app: mysql
strategy:
type: Recreate
template:
metadata:
labels:
app: mysql
spec:
containers:
- image: mysql:8.0.26
name: mysql
env:
# Use secret in real usage
- name: MYSQL_ROOT_PASSWORD
value: password
- name: MYSQL_ROOT_HOST
value: "%"
ports:
- containerPort: 3306
name: mysql
volumeMounts:
- name: mysql-persistent-storage
mountPath: /var/lib/mysql
volumes:
- name: mysql-persistent-storage
emptyDir: {}
# Following the original example, comment the emptyDir and uncomment the following if you have StorageClass installed.
# persistentVolumeClaim:
# claimName: mysql-pv-claim
No change to the client connect except for the image tag:
kubectl run -it --rm --image=mysql:8.0.26 --restart=Never mysql-client -- mysql -h mysql -ppassword
Test with show databases;:
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
+--------------------+
4 rows in set (0.00 sec)