Access MySQL Kubernetes Deployment in MySQL Workbench - mysql

I deployed a MySQL pod with the example from the kubernetes website: https://kubernetes.io/docs/tasks/run-application/run-single-instance-stateful-application/
I can access the pod from the pod network but not from outside the cluster, how can I achieve this? I would want to access the service via MySQL Workbench for easier editing of the Database.
I already tried to setup a NodePort service like this:
apiVersion: v1
kind: Service
metadata:
name: mysql
spec:
ports:
- port: 3306
targetPort: 3006
nodePort: 30003
selector:
app: mysql
type: NodePort
with the goal to access the service at :30003 but that does not work.


apiVersion: v1
kind: Service
metadata:
name: mysql
spec:
ports:
- port: 3306
targetPort: 3006
nodePort: 30003
selector:
app: mysql
type: NodePort
the targetPort is 3006 instead of 3306, it was a typo.

Related

Exposing pod to outside world with MySQL database in Azure Kubernetes Service

Hi I've deployed single MySQL db instance in Azure via the YAML file in Azure Kubernetes service. I can get into the container via CLI when I'm inside my cluster. I would like to connect with db instance via external client like MySQL Workbench or Sqlelectron or others, outside the cluster. As I found out it's possible via correctly exposing DB instance by Service configuration.
My deployment of single instance MySQL DB instance is:
apiVersion: v1
kind: Service
metadata:
name: mysql-db-testing-service
namespace: testing
spec:
type: ClusterIP
ports:
- port: 3306
#targetPort: 3306
selector:
app: mysql-db-testing
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: mysql-db-testing
namespace: testing
spec:
selector:
matchLabels:
app: mysql-db-testing
replicas: 1
strategy:
type: Recreate
template:
metadata:
labels:
app: mysql-db-testing
spec:
containers:
- name: mysql-db-container-testing
image: mysql:8.0.31
env:
- name: MYSQL_ROOT_PASSWORD
value: test12345
ports:
- containerPort: 3306
name: mysql-port
volumeMounts:
- mountPath: "/var/lib/mysql"
name: mysql-persistent-storage
volumes:
- name: mysql-persistent-storage
persistentVolumeClaim:
claimName: azure-managed-disk-pvc-mysql-testing
nodeSelector:
env: preprod
As I've mentioned I can get to the container via CLI:
Console output regarding the working pod with db looks like:
Console output regarding the service:
Is there something missing in my deployment YAML file or maybe there are missing some fields? How can I expose db to the outside world? I would be grateful for help.

You are using ClusterIP service(line 7). The kubernetes ClusterIP service is not made to allow you to access a pod outside of the cluster. ClusterIP just provide a way to have a not changing IP for other internal services to access your pod.
You should use instead Loadbalanacer.
Cf https://stackoverflow.com/a/48281728/8398523 for differences

You have used the type: ClusterIP so it won't expose the MYSQL outside the cluster ideally, your Microservices running in the cluster will be able to access it however you can not use it externally.
To expose the service we generally have to use the type: LoadBalancer. It will directly expose your MySQL service internet and from your local workbench, you can connect to DB running on K8s.
If you really don't want to expose the MySQL service directly to internet you can deploy the adminer.
So traffic will flow like
internet > adminer > internal communication > MySQL service > MySQL POD
YAML file to deploy and get the UI output directly in the browser, it will ask of MySQL DB username, password, Host (mysql-db-testing-service.testing.svc.cluster.local) to connect
apiVersion: apps/v1
kind: Deployment
metadata:
name: adminer
labels:
app: adminer
spec:
selector:
matchLabels:
app: adminer
template:
metadata:
labels:
app: adminer
spec:
containers:
- name: adminer
image: adminer:4.6.3
ports:
- containerPort: 8080
env:
- name: ADMINER_DESIGN
value: "pappu687"
---
apiVersion: v1
kind: Service
metadata:
name: adminer-svc
spec:
type: ClusterIP(Internally to cluster)/LoadBalancer (Expose to internet)
selector:
app: adminer
ports:
- protocol: TCP
port: 8080
targetPort: 8080
Port-forward for local access or use service type: LoadBalancer
kubectl port-forward svc/adminer-svc 8080:8080
Open localhost:8080 in browser

how can i access mysql on kubernetes cluster?

I have deployed MySQL in my Kubernetes cluster. It works like fine. But I am not aware of how to access or connect MySQL service to other applications. I found that MySQL deployment is not browser-supported.
when I call the MySQL server on the browser using IP:nodeport, I found the following error
J���
5.7.37����!bo.;�ÿÿ�ÿÁ����������rBPvNbCJ�mysql_native_password�!��ÿ„#08S01Got packets out of order
I can access MySQL server through Kubernetes dashboard's pod shell using MySQL user and password

You can try deploying the MySQL client on Kubernetes and connect using it.
MySQL client like : Adminer, phpMyadmin etc
Adminer example :
apiVersion: apps/v1
kind: Deployment
metadata:
name: adminer
labels:
app: adminer
spec:
selector:
matchLabels:
app: adminer
template:
metadata:
labels:
app: adminer
spec:
containers:
- name: adminer
image: adminer:4.6.3
ports:
- containerPort: 8080
env:
- name: ADMINER_DESIGN
value: "pappu687"
---
apiVersion: v1
kind: Service
metadata:
name: adminer-svc
spec:
selector:
app: adminer
ports:
- protocol: TCP
port: 8080
targetPort: 8080
You can expose this deployment with service type Nodeport or Port forwarding.
kubectl port-forward svc/adminer-svc 8080:8080
Open the localhost:8080
Once the service is exposed you can access the UI in the browser and from there you can access the MySQL database over the service name.
Read more about adminer : https://www.adminer.org/

SQLAlchemy cannot connect to Mysql server on localhost in Kubernetes

I deployed a mysql service in Kubernetes and created a database(db1) and a custom user('foo'#'localhost' identified by 'bar') with all privileges. I can verify it.
but somehow my Flask application cannot connect to it. So, I turned on the debug mode and got
sqlalchemy.exc.OperationalError
sqlalchemy.exc.OperationalError: (pymysql.err.OperationalError) (2003, "Can't connect to MySQL server on 'localhost' ([Errno 99] Address not available)")
(Background on this error at: http://sqlalche.me/e/13/e3q8)
This never happens in Linux machines. This is my DATABASE_URL mysql+pymysql://foo:bar#localhost:3306/db1
Is there anything I am doing wrong? I am new to kubernetes, I don't even know how to go about debugging it. Please let me know if I am not providing enough information.
Thank you.
[EDITED]
mysql-deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: mysql
labels:
app: mysql
spec:
replicas: 1
selector:
matchLabels:
app: mysql
template:
metadata:
labels:
app: mysql
spec:
containers:
- image: mysql:5.6
name: mysql
env:
- name: MYSQL_ROOT_PASSWORD
value: "123"
ports:
- containerPort: 3306
name: mysql
volumeMounts:
- name: mysql-persistent-storage
mountPath: /var/lib/mysql
volumes:
- name: mysql-persistent-storage
persistentVolumeClaim:
claimName: mysql-volumeclaim
mysql-service.yaml
apiVersion: v1
kind: Service
metadata:
name: mysql
labels:
app: mysql
spec:
type: ClusterIP
ports:
- port: 3306
selector:
app: mysql

mysql service as type: ExternalName is not able to conenct from other namespace in Kubernetes ( minikube )

I have a mysql service deployed in namespace : mysqlns. Following is the service defination.
apiVersion: v1
kind: Service
metadata:
name: mysql
namespace: mysqlns
labels:
app: mysql
spec:
clusterIP: None
ports:
- port: 3306
name: tcp
targetPort: 3306
selector:
app: mysql
type: ClusterIP
Now I do have a spring boot application deployed in default namespace
That service defination is as below
---
apiVersion: v1
kind: Service
metadata:
name: opapolicystoreapp-t1
labels:
app: opapolicystoreapp-t1
service: opapolicystoreapp-t1
spec:
ports:
- port: 8484
name: http
selector:
app: opapolicystoreapp-t1
---
kind: Service
apiVersion: v1
metadata:
name: mysql
namespace: default
spec:
type: ExternalName
externalName: mysql.mysqlns.svc.cluster.local
ports:
- port: 3306
---
Mysql service in mysqlns is deployed properly and running
but when I am trying to deploy my application in default namespace .. service type ExternalName never came up .. and it is not running, hence my application is also not able to connect to mysql external service.
I am using springboot application property file to connect to service
spring:
datasource:
url: jdbc:mysql://mysql/policyds
username: xxxx
password: XXXX
Not able to find the mistake here.

How do I access MySQL as a Service on Kubernetes?

I have the following deployment...
---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: mysql-data-disk
spec:
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 1Gi
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: mysql-deployment
labels:
app: mysql
spec:
replicas: 1
selector:
matchLabels:
app: mysql
template:
metadata:
labels:
app: mysql
spec:
containers:
- name: mysql
image: mysql:5.7
ports:
- containerPort: 3306
volumeMounts:
- mountPath: "/var/lib/mysql"
subPath: "mysql"
name: mysql-data
env:
- name: MYSQL_ROOT_PASSWORD
valueFrom:
secretKeyRef:
name: mysql-secrets
key: ROOT_PASSWORD
volumes:
- name: mysql-data
persistentVolumeClaim:
claimName: mysql-data-disk
This works great I can access the db like this...
kubectl exec -it mysql-deployment-<POD-ID> -- /bin/bash
Then I run...
mysql -u root -h localhost -p
And I can log into it. However, when I try to access it as a service by using the following yaml...
---
apiVersion: v1
kind: Service
metadata:
name: mysql-service
spec:
selector:
app: mysql
ports:
- protocol: TCP
port: 3306
targetPort: 3306
I can see it by running this kubectl describe service mysql-service I get...
Name: mysql-service
Namespace: default
Labels: <none>
Annotations: kubectl.kubernetes.io/last-applied-configuration:
{"apiVersion":"v1","kind":"Service","metadata":{"annotations":{},"name":"mysql-service","namespace":"default"},"spec":{"ports":[{"port":33...
Selector: app=mysql
Type: ClusterIP
IP: 10.101.1.232
Port: <unset> 3306/TCP
TargetPort: 3306/TCP
Endpoints: 172.17.0.4:3306
Session Affinity: None
Events: <none>
and I get the ip by running kubectl cluster-info
#kubectl cluster-info
Kubernetes master is running at https://192.168.99.100:8443
KubeDNS is running at https://192.168.99.100:8443/api/v1/namespaces/kube-system/services/kube-dns:dns/proxy
but when I try to connect using Oracle SQL Developer like this...
It says it cannot connect.
How do I connect to the MySQL running on K8s?

Service type ClusterIP will not be accessible outside of Pod network.
If you don't have LoadBalancer option, then you have to use either Service type NodePort or kubectl port-forward

You need your mysql service to be of Type NodePort instead of ClusterIP to access it outside Kubernetes.
Use the Node Port in your client config
Example Service:
apiVersion: v1
kind: Service
metadata:
name: mysql-service
spec:
type: NodePort
selector:
app: mysql
ports:
- protocol: TCP
port: 3306
nodePort: 30036
targetPort: 3306
So then you can use the port: 30036 in your client.