I have a kubernetes service, and I wanna it to target pods.
This is how I define my service:
apiVersion: v1
kind: Service
metadata:
name: my-service
spec:
selector:
app: myapp
ports:
- port: 77
targetPort: 80
nodePort: 32766
type: NodePort
and this is how I define my deployment:
apiVersion: apps/v1
kind: Deployment
metadata:
name: my-deployment
spec:
replicas: 5
selector:
matchLabels:
app: myapp
template:
metadata:
name: my-pod
labels:
app: myapp
spec:
containers:
- name: httd
image: httpd
imagePullPolicy: Always
ports:
- containerPort: 80
Basically what I did is linking port 80 in the pod to port 77 in the service to port 32766 in the node.
I already know that my container is running on port 80 because If I do this:
docker run -p 8989:80 httpd
and ask for localhost:8989 I can see the page.
If I do kubetctl get services I get:
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 46h
my-service NodePort 10.100.157.161 <none> 77:32766/TCP 20m
I tried calling:
10.100.157.161:32766
10.100.157.161:77
But both give connection error.
What did I miss?
Use the below YAMLs. It works
apiVersion: apps/v1
kind: Deployment
metadata:
labels:
app: myapp
name: my-deployment
spec:
replicas: 5
selector:
matchLabels:
app: myapp
template:
metadata:
labels:
app: myapp
spec:
containers:
- image: httpd
name: httpd
imagePullPolicy: Always
ports:
- containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
name: my-service
spec:
selector:
app: myapp
ports:
- port: 77
targetPort: 80
nodePort: 32766
type: NodePort
master $ kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 15m
my-service NodePort 10.110.219.232 <none> 77:32766/TCP 12s
master $
master $
master $ curl 10.110.219.232:77
<html><body><h1>It works!</h1></body></html>
master $
master $
master $ curl $(hostname -i):32766
<html><body><h1>It works!</h1></body></html>
master $
Related
this is my pod.yaml file
apiVersion: v1
kind: Pod
metadata:
name: voting-app-pod
labels:
name: voting-app-pod
app: demo-voting-app
spec:
containers:
- name: voting-app
image: kodekloud/examplevotingapp_vote:v1
ports:
- containerPort: 80
and this is my service.yaml file
apiVersion: v1
kind: Service
metadata:
name: voting-service
labels:
name: voting-service
app: demo-voting-app
spec:
type: NodePort
ports:
- port: 80
targetPort: 80
nodePort: 30004
selector:
name: voting-app-pod
app: demo-voting-app
after executing
kubectl get pods,svc
i get
NAME READY STATUS RESTARTS AGE
pod/voting-app-pod 1/1 Running 0 37m
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 11d
service/voting-service NodePort 10.107.145.225 <none> 80:30004/TCP 6m45s
I tried to a access the service trough http://localhost:30004 and also i tried
http://127.0.0.1:30004
with no success
Please have selector and template label declaration in deployment as below. For more details on the attributes, refer kubernetes documentation
spec:
selector:
matchLabels:
app: demo-voting-app
template:
metadata:
labels:
app: demo-voting-app
And in service as below
selector:
app: demo-voting-app
I am trying to use minikube to deploy a sample flask app. But getting 503 nginx error. Please note I am able to access the app using the Nodeport service config.
I checked with minikube IP which is mapped to local host and tried to access the app, but getting 503 error. Not sure if I missed anything. I enable the minikube addons for nginx.
Here are my files -
deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: flaskapp-deployment
labels:
app: flaskapp
spec:
replicas: 1
selector:
matchLabels:
app: flaskapp
template:
metadata:
labels:
app: flaskapp
spec:
containers:
- name: flaskapp
image: <repo>/sample-flask-app:1.0
ports:
- containerPort: 5000
env:
- name: APPLICATION_SETTINGS
value: prd_config.py
imagePullSecrets:
- name: jfrog-secret
Service.yaml
apiVersion: v1
kind: Service
metadata:
name: flaskapp-service
labels:
app: flaskapp
spec:
selector:
app: flaskapp
ports:
- protocol: TCP
port: 5000
targetPort: 5000
Ingress.yaml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: flaskapp-ingress
labels:
app: flaskapp
spec:
defaultBackend:
service:
name: default-http-backend
port:
number: 80
rules:
- host: mydashboard.com
http:
paths:
- path: /
pathType: Prefix
backend:
service:
name: flaskapp-service
port:
number: 5000
Ingress status :
minikube kubectl -- get ingress flaskapp-ingress
NAME CLASS HOSTS ADDRESS PORTS AGE
flaskapp-ingress nginx mydashboard.com localhost 80 18m
Cluster status:
minikube kubectl -- get all
NAME READY STATUS RESTARTS AGE
pod/flaskapp-deployment-7f59f96fd5-j9mv9 1/1 Running 1 (103m ago) 15h
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/flaskapp-deployment ClusterIP 10.103.143.58 <none> 5000/TCP 34m
service/flaskapp-service ClusterIP 10.111.242.99 <none> 5000/TCP 15h
service/kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 35h
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/flaskapp-deployment 1/1 1 1 15h
NAME DESIRED CURRENT READY AGE
replicaset.apps/flaskapp-deployment-7f59f96fd5 1 1 1 15h
I built a k8s cluster with help of this guide: rpi+k8s. I got some basic nginx service up and running and and I can curl from master node to worker node to get the nginx welcome page content using:
k exec nginx-XXX-XXX -it -- curl localhost:80
I tried following suggestions in the following SO posts:
link 1
link 2
However, I still can't access a simple nginx service on the worker node from my local computer (linux). I used, NODE IP:NODE PORT. I also installed kubefwd and ran, sudo kubefwd svc -n nginx-ns but I don't see the expected output where it would show the port forwards. Any help would be appreciated. Thanks.
Output:
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/nginx-svc NodePort 10.101.19.230 <none> 80:32749/TCP 168m
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/nginx 3/3 3 3 168m
NAME DESIRED CURRENT READY AGE
replicaset.apps/nginx-54485b444f 3 3 3 168m
And here is the yaml file:
kind: Namespace
apiVersion: v1
metadata:
name: nginx-ns
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx
namespace: nginx-ns
spec:
selector:
matchLabels:
app: nginx
replicas: 3
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.19-alpine
ports:
- name: nginxport
containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
name: nginx-svc
namespace: nginx-ns
labels:
app: nginx
spec:
selector:
app: nginx
ports:
- protocol: TCP
name: nginxport
port: 80
targetPort: 80
nodePort: 32749
type: NodePort
selector:
app: backend
You need to update your service nginx-svc where you have used two selector.
remove below part:
selector:
app: backend
Updated service.yaml:
apiVersion: v1
kind: Service
metadata:
name: nginx-svc
namespace: nginx-ns
labels:
app: nginx
spec:
selector:
app: nginx
ports:
- protocol: TCP
name: nginxport
port: 80
targetPort: 80
nodePort: 32749
type: NodePort
Then, Try this one for port-forwarding.
kubectl port-forward -n nginx-ns svc/nginx-svc 8080:80
Template is like this:
kubectl port-forward -n <namespace> svc/<svc_name> <local_port>:<svc_port>
Then try in the browser with 127.0.0.1:8080 or localhost:8080
I have created a k8s deployment and service yaml for a static website. External IP address is also resolved in kubernetes service. But when I try to access the website through curl or browser, it returns connection timed out.
Dockerfile:
FROM nginx:alpine
COPY . /usr/share/nginx/html
K8s deployment yml:
apiVersion: apps/v1
kind: Deployment
metadata:
name: ohno-website
labels:
app: ohno-website
spec:
replicas: 1
selector:
matchLabels:
app: ohno-website
template:
metadata:
labels:
app: ohno-website
spec:
containers:
- name: ohno-website
image: gkganeshr/ohno-website:v0.1
imagePullPolicy: Always
ports:
- containerPort: 80
k8s service yml:
apiVersion: v1
kind: Service
metadata:
name: ohno-website
spec:
type: LoadBalancer
ports:
- protocol: TCP
port: 80
targetPort: 9376
selector:
app: ohno-website
ohno_fooserver#cloudshell:~ (fourth-webbing-279817)$ kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.16.0.1 <none> 443/TCP 8h
ohno-website LoadBalancer 10.16.12.162 34.70.213.174 80:31977/TCP 7h4m
The target port defined in the service defition YAML is incorrect. It should match with container port from pod definition in deployment YAML
targetPort: 9376
should be changed to
targetPort: 80
I'm doing a deployment on the GKE service and I find that when I try to access the page the message
ERR_CONNECTION_REFUSED
I have defined a load balancing service for deployment and the configuration is as follows.
This is the .yaml for the deployment
apiVersion: apps/v1
kind: Deployment
metadata:
name: bonsai-onboarding
spec:
selector:
matchLabels:
app: bonsai-onboarding
replicas: 2
template:
metadata:
labels:
app: bonsai-onboarding
spec:
containers:
- name: bonsai-onboarding
image: "eu.gcr.io/diaphanum/onboarding-iocash-master_web:v1"
ports:
- containerPort: 3000
This is the service .yaml file.
apiVersion: v1
kind: Service
metadata:
name: lb-onboarding
spec:
type: LoadBalancer
selector:
app: bonsai-onboarding
ports:
- protocol: TCP
port: 3000
targetPort: 3000
This working fine, and all is green in GKE :)
kubectl get pods,svc
NAME READY STATUS RESTARTS AGE
pod/bonsai-onboarding-8586b9b699-flhbn 1/1 Running 0 3h23m
pod/bonsai-onboarding-8586b9b699-p9sn9 1/1 Running 0 3h23m
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP XX.xx.yy.YY <none> 443/TCP 29d
service/lb-onboarding LoadBalancer XX.xx.yy.YY XX.xx.yy.YY 3000:32618/TCP 3h
Then when i tried to connect the error is ERR_CONNECTION_REFUSED
I think is about the network because y did the next test from my local machine
Ping [load balancer IP] ---> Correct
Telnet [Load Balancer IP] 3000 ---> Correct
From cloud shell i forward the port 3000 to 8080 and in other cloudShell make a Curl http://localhost:8080, and work fine.
Any idea about the problem?
Thanks in advance
I've changed a little bit your deployment to check it on my cluster because your image was unreachable:
deployment:
apiVersion: apps/v1
kind: Deployment
metadata:
name: bonsai-onboarding
spec:
selector:
matchLabels:
app: bonsai-onboarding
replicas: 2
template:
metadata:
labels:
app: bonsai-onboarding
spec:
containers:
- name: bonsai-onboarding
image: nginx:latest
ports:
- containerPort: 80
service:
apiVersion: v1
kind: Service
metadata:
name: lb-onboarding
spec:
type: LoadBalancer
selector:
app: bonsai-onboarding
ports:
- protocol: TCP
port: 3000
targetPort: 80
and it works out of the box:
kubectl get pods,svc
NAME READY STATUS RESTARTS AGE
pod/bonsai-onboarding-7bdf584499-j2nv7 1/1 Running 0 6m58s
pod/bonsai-onboarding-7bdf584499-vc7kh 1/1 Running 0 6m58s
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP 10.XXX.XXX.1 <none> 443/TCP 8m35s
service/lb-onboarding LoadBalancer 10.XXX.XXX.230 35.XXX.XXX.235 3000:31637/TCP 67s
and I'm able reach 35.XXX.XXX.235:3000 from any IP:
Welcome to nginx!
...
Thank you for using nginx.
You can check if your app is reachable using this command:
nmap -Pn $(kubectl get svc lb-onboarding -o jsonpath='{.status.loadBalancer.ingress[*].ip}')
Maybe the cause of your problem with "ERR_CONNECTION_REFUSED" in configuration of your image? I found no problem with your deployment and load balancer configuration.
Ensure containerPort is defined in the spec of the deployment/statefulset/pod and the application is listening on that port. Also ensure your firewall rules are not blocking the nodeport.
gcloud compute firewall-rules create myservice --allow tcp:3000