It's been some days since I have started to learn Kubernetes. I am a noob in this and don't have any troubleshooting skills or any experience this is my first lab and however I am stuck in my first lab. Now the problem is this I have a VMware workstation where I have hosted my centos box in that box I have installed docker minikube kubectl KVM and then started the lab.
There are two object files which will be shown below ...
vi client-pod.yml
apiVersion: v1
kind: Pod
metadata:
name: client-pod
labels:
components: web
spec:
containers:
- name: client
image: stephengrider/multi-client
ports:
- containerPort: 3000
vi client-pod.service
apiVersion: v1
kind: Service
metadata:
name: client-node-port
spec:
type: NodePort
ports:
- port: 3050
targetPort: 3000
nodePort: 31515
selector:
component: web
after this I use the
minikube start --driver=kvm
Then after loading it starts
Then I use these commands
kubectl apply -f client-pod.yml
kubectl apply -f client-pod.service
So after this I use the
minikube ip
I get a IP:192.168.39.107
Then in browser of host when I use http://192.168.39.107:31515
It shows request not completed or something like that
Can anyone tell me whats going on
Your Pod labels and Service selector aren't same.
Either use components: web or component: web in both pod and service.
apiVersion: v1
kind: Pod
metadata:
name: client-pod
labels:
component: web # updated labels key
...
apiVersion: v1
kind: Service
metadata:
name: client-node-port
spec:
type: NodePort
ports:
- port: 3050
targetPort: 3000
nodePort: 31515
selector:
component: web # it should be same as pod labels
This should solve your issue.
Related
I am running a minikube cluster (driver docker) on amazon linux 2. I have a pod and service created. I'm having issues accessing the service from my browser
#pod.yaml
apiVersion: v1
kind: Pod
metadata:
name: webapp
labels:
app: webapp
spec:
containers:
- name: webapp
image: richardchesterwood/k8s-fleetman-webapp-angular:release0
#service.yaml
apiVersion: v1
kind: Service
metadata:
name: fleetman-webapp
spec:
selector:
app: webapp
ports:
- name: http
port: 80
nodePort: 30080
type: NodePort
When i try and hit the public ip and node port in the browser, it times out. What am i missing here?
I have a running pod that was created with the following pod-definition.yaml:
apiVersion: v1
kind: Pod
metadata:
name: microservice-one-pod-name
labels:
app: microservice-one-app-label
type: front-end
spec:
containers:
- name: microservice-one
image: vismarkjuarez1994/microserviceone
ports:
- containerPort: 2019
I then created a Service using the following service-definition.yaml:
kind: Service
apiVersion: v1
metadata:
name: microserviceone-service
spec:
ports:
- port: 30008
targetPort: 2019
protocol: TCP
selector:
app: microservice-one-app-label
type: NodePort
I then ran kubectl describe node minikube to find the Node IP I should be connecting to -- which yielded:
Addresses:
InternalIP: 192.168.49.2
Hostname: minikube
But I get no response when I run the following curl command:
curl 192.168.49.2:30008
The request also times out when I try to access 192.168.49.2:30008 from a browser.
The pod logs show that the container is up and running. Why can't I access my Service?
The problem is that you are trying to access your service at the port parameter which is the internal port at which the service will be exposed, even when using NodePort type.
The parameter you were searching is called nodePort, which can optionally be specified together with port and targetPort. Quoting the documentation:
By default and for convenience, the Kubernetes control plane will
allocate a port from a range (default: 30000-32767)
Since you didn't specify the nodePort, one in the range was automatically picked up. You can check which one by:
kubectl get svc -owide
And then access your service externally at that port.
As an alternative, you can change your service definition to be something like:
kind: Service
apiVersion: v1
metadata:
name: microserviceone-service
spec:
ports:
- port: 30008
targetPort: 2019
nodePort: 30008
protocol: TCP
selector:
app: microservice-one-app-label
type: NodePort
But take in mind that you may need to delete your service and create it again in order to change the nodePort allocated.
I think you missed the Port in your service:
apiVersion: v1
kind: Pod
metadata:
name: microservice-one-pod-name
labels:
app: microservice-one-app-label
type: front-end
spec:
containers:
- name: microservice-one
image: vismarkjuarez1994/microserviceone
ports:
- containerPort: 2019
and your service should be like this:
kind: Service
apiVersion: v1
metadata:
name: microserviceone-service
spec:
ports:
- port: 2019
targetPort: 2019
nodePort: 30008
protocol: TCP
selector:
app: microservice-one-app-label
type: NodePort
You can access to your app after enabling the Minikube ingress if you want trying Ingress with Minikube.
minikube addons enable ingress
I started implementing the Kuberenetes for my simple app. I am facing issue when i use NodePort. IF I use LoadBalancer I can open my url. If I use NodePort it will take long time for trying to load and getting error connection refused. Below is my simple yaml file.
> POD yaml
apiVersion: v1
kind: Pod
metadata:
name: pod-webapp
labels:
app: webapp
spec:
containers:
- name: app
image: mydockerimage_xxx
> service.yaml
kind: Service
apiVersion: v1
metadata:
# Unique key of the Service instance
name: service-webapp
spec:
ports:
# Accept traffic sent to port 80
- name: http
port: 80
nodePort: 30080
selector:
app: webapp
type: NodePort
what I found something in GitHub : Kubernetes NodePort which solved my issue partially.
I am trying to setup a very simple monitoring cluster for my k8s cluster. I have successfully created prometheus pod and is running fine.
When I tried to create grafana pod the same way, its not accessible through the node port.
My Grafana deploy file is-
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
name: grafana-deployment
namespace: monitoring
spec:
replicas: 1
template:
metadata:
labels:
app: grafana-server
spec:
containers:
- name: grafana
image: grafana/grafana:5.1.0
ports:
- containerPort: 3000
And Service File is --
apiVersion: v1
kind: Service
metadata:
name: grafana-service
namespace: monitoring
spec:
selector:
app: grafana-server
type: NodePort
ports:
- port: 3000
targetPort: 3000
Note- When I am creating a simple docker container on the same host using same image, its working fine.
I have come to know that my servers provider had not enabled these ports (like grafana-3000, kibana-5601). Never thought of this since i am using these servers from quite a long time and never faced such blocker. They implemented these rules recently.
Well, after some port approvals, I tried the same config again and it worked like a charm.
I'm running a simple spring microservice project with Minikube. I have two projects: lucky-word-client (on port 8080) and lucky-word-server (on port 8888). But I can't communicate client with server. Infact if lucky-word-client communicates with lucky-word-server, the result is the word "Evviva", else the word is "Default". When I run on terminal: minikube service lucky-client the output is Default, instead of Evviva. I want communicate client with server through DNS. I saw the guide: https://kubernetes.io/docs/concepts/services-networking/dns-pod-service/ but without success. How i can modify the service or pods to have the link between client and server?
This is the pod of lucky-word-client:
apiVersion: v1
kind: Pod
metadata:
name: lucky-client
namespace: default
spec:
containers:
- image: lucky-client-img
imagePullPolicy: IfNotPresent
name: lucky-client
This is the pod of lucky-word-server:
apiVersion: v1
kind: Pod
metadata:
name: lucky-server
namespace: default
spec:
containers:
- image: lucky-server-img
imagePullPolicy: IfNotPresent
name: lucky-server
This is the service, where the lucky-word-client communicate with lucky-word-server:
kind: Service
apiVersion: v1
metadata:
name: lucky-client
spec:
selector:
app: lucky-client
ports:
- protocol: TCP
targetPort: 8080
port: 80
type: NodePort
If you want to have DNS based service discovery to communicate with the server follow the below steps:
Enable kube-dns addon via minikube addons enable kube-dns command. This will enable the service discovery in your kubernetes cluster.
Make sure that kube-dns addon is enable using minikube addons list command.
In your client application code change the server URL endpoint to the following : http://lucky-server:8888. "lucky-server" is the metadata.name property of your Kubernetes server service yaml definition.
Or else instead of lucky-server you can use fully qualified name lucky-server.default.svc.cluster.local in the server URL since you are deploying your service in default namespace.
You need a service for your lucky-server :
kind: Service
apiVersion: v1
metadata:
name: lucky-server
spec:
selector:
app: lucky-server
ports:
- protocol: TCP
targetPort: 8888
port: 80
type: NodePort