Can't connect with my frontend with kubectl - kubernetes

With kubernetes, I created an ingress with a service like these :
apiVersion: networking.k8s.io/v1beta1
kind: Ingress
metadata:
name: syntaxmap2
spec:
backend:
serviceName: testsvc
servicePort: 3000
The service testsvc is already created.
I created a frontend service like these :
apiVersion: v1
kind: Service
metadata:
name: syntaxmapfrontend
spec:
selector:
app: syntaxmap
tier: frontend
ports:
- protocol: "TCP"
port: 7000
targetPort: 7000
type: LoadBalancer
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: syntaxmapfrontend
spec:
selector:
matchLabels:
app: syntaxmap
tier: frontend
track: stable
replicas: 1
template:
metadata:
labels:
app: syntaxmap
tier: frontend
track: stable
spec:
containers:
- name: nginx
image: "gcr.io/google-samples/hello-frontend:1.0"
lifecycle:
preStop:
exec:
command: ["/usr/sbin/nginx","-s","quit"]
When I do these command :
kubectl describe ingress syntaxmap2
I have an Ip adress than i can put in my browser and I have an answer
But when I do these command :
kubctl describe service syntaxmapfrontend
I have an Ip adress with a port and when I try to connect to it with curl, I have a time out.
How can I connect to my kubernet frontend with curl ?

The service is accessible only from within the k8s cluster. You either need to change the type of address from ClusterIP to NodeIP, or use something like kubectl port-forward or kubefwd.
If you need more detailed advice, you'll need to post the output of those commands, or even better, show us how you created the objects.

I have found a way.
I write :
minikube service syntaxmapfrontend
And it open a browser with the right URL.

Related

load balancer not reachable after creating as service

I have deployed simple app -NGINX and a Load balancer service in Kubernetes.
I can see that pods are running as well as service but calling Loadbalancer external IP is givings server error -site can't be reached .Any suggestion please
app.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deployment
spec:
selector:
matchLabels:
app: nginx
replicas: 2 # tells deployment to run 2 pods matching the template
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.14.2
ports:
- containerPort: 80
Service.Yaml:
apiVersion: v1
kind: Service
metadata:
name: nginx-service
spec:
type: LoadBalancer
ports:
- port: 80
selector:
app: nginx
P.S. -Attached outcome from terminal.
If you are using Minikube to access the service then you might need to run one extra command. But if this is on a cloud provider then you have an error in your service file.
Please ensure that you put two space in yaml file but your indentation of the yaml file is messed up as you have only added 1 space. Also you made a mistake in the last line of service.yaml file.
apiVersion: v1
kind: Service
metadata:
name: nginx-service
spec:
type: LoadBalancer
ports:
- port: 80
selector:
app: nginx

Why can't I curl endpoint on GCP?

I am working my way through a kubernetes tutorial using GKE, but it was written with Azure in mind - tho it has been working ok so far.
The first part where it has not worked has been with exercises regarding coreDNS - which I understand does not exist on GKE - it's kubedns only?
Is this why I can't get a pod endpoint with:
export PODIP=$(kubectl get endpoints hello-world-clusterip -o jsonpath='{ .subsets[].addresses[].ip}')
and then curl:
curl http://$PODIP:8080
My deployment is definitely on the right port:
ports:
- containerPort: 8080
And, in fact, the deployment for the tut is from a google sample.
Is this to do with coreDNS or authorisation/needing a service account? What can I do to make the curl request work?
Deployment yaml is:
apiVersion: apps/v1
kind: Deployment
metadata:
name: hello-world-customdns
spec:
replicas: 3
selector:
matchLabels:
app: hello-world-customdns
template:
metadata:
labels:
app: hello-world-customdns
spec:
containers:
- name: hello-world
image: gcr.io/google-samples/hello-app:1.0
ports:
- containerPort: 8080
dnsPolicy: "None"
dnsConfig:
nameservers:
- 9.9.9.9
---
apiVersion: v1
kind: Service
metadata:
name: hello-world-customdns
spec:
selector:
app: hello-world-customdns
ports:
- port: 80
protocol: TCP
targetPort: 8080
Having a deeper insight on what Gari comments, when exposing a service outside your cluster, this services must be configured as NodePort or LoadBalancer, since ClusterIP only exposes the Service on a cluster-internal IP making the service only reachable from within the cluster, and since Cloud Shell is a a shell environment for managing resources hosted on Google Cloud, and not part of the cluster, that's why you're not getting any response. To change this, you can change your yaml file with the following:
apiVersion: apps/v1
kind: Deployment
metadata:
name: hello-world-customdns
spec:
replicas: 3
selector:
matchLabels:
app: hello-world-customdns
template:
metadata:
labels:
app: hello-world-customdns
spec:
containers:
- name: hello-world
image: gcr.io/google-samples/hello-app:1.0
ports:
- containerPort: 8080
dnsPolicy: "None"
dnsConfig:
nameservers:
- 9.9.9.9
---
apiVersion: v1
kind: Service
metadata:
name: hello-world-customdns
spec:
selector:
app: hello-world-customdns
type: NodePort
ports:
- port: 80
protocol: TCP
targetPort: 8080
After redeploying your service, you can run command kubectl get all -o wide on cloud shell to validate that NodePort type service has been created with a node and target port.
To test your deployment just throw a CURL test to he external IP from one of your nodes incluiding the node port that was assigned, the command should look like something like:
curl <node_IP_address>:<Node_port>

I expose my pod in kubernetes but I canĀ“t seem to establish a connection with it

I am trying to expose a deployment I made on minikube:
apiVersion: apps/v1
kind: Deployment
metadata:
name: deployment-test
labels:
app: debian
spec:
replicas: 1
selector:
matchLabels:
app: debian
strategy: {}
template:
metadata:
labels:
app: debian
spec:
containers:
- image: agracia10/debian_bash:latest
name: debian
ports:
- containerPort: 8006
resources: {}
restartPolicy: Always
status: {}
I decided to follow was is written on here
I try to expose the deployment using the following command:
kubectl expose pod deployment-test-8497d6f458-xxhgm --type=NodePort --port=8080 --target-port=80
but when I try to then access the service created by the expose command, using the url provided by
minikube service deployment-test-8497d6f458-xxhgm --url
it throws an error using packetsender to try and connect to the service:
packet sender log
Im not really sure what the reason for this could be, I think it has something to do with the fact that when I get the services it says on the external ip field. Also, when I try and retrieve the node IP using minikube ip it gives an address, but when the minikube service --url it gives the 127.0.0.1 address. In any case, using either one does not work.
it's not working due to a port configuration mismatch.
You deployment container running on the 8006 but you have exposed the 8080 and your target port is : --target-port=80
so due to this it's not working.
Ideal flow of traffic goes like :
service (node port, cluster IP or any) > Deployment > PODs
Below sharing the example for deployment and service
apiVersion: apps/v1
kind: Deployment
metadata:
name: blog-app-server-instance
labels:
app: blog-app
spec:
replicas: 1
selector:
matchLabels:
app: blog-app
template:
metadata:
labels:
app: blog-app
spec:
containers:
- name: agracia10/debian_bash:latest
image: blog-app-server
ports:
- containerPort: 8006
---
apiVersion: v1
kind: Service
metadata:
name: blog-app-service
labels:
app: blog-app
spec:
selector:
app: blog-app
type: NodePort
ports:
- port: 80
nodePort: 31364
targetPort: 8006
protocol: TCP
name: HTTP
so things I have changed are image and target port.
Once your Node port service is up and running you will send the request on Port 80 or 31364
i will redirect the request internally to the target port which is 8006 for the container also.
Using this command you exposed your deployment on wrong target point
kubectl expose pod deployment-test-8497d6f458-xxhgm --type=NodePort --port=8080 --target-port=80
ideally it should be 8006
As I know the simplest way to expose the deployment to service we can run this command, you don't expose the pod but expose the deployment.
kubectl expose deployment deployment-test --port 80

Kubernetes MetalLB External IP not reachable from browser

I have a nginx deployment with service type LoadBalancer.
I got a external IP which is accessible from master and worker node.
I am not able to access it from browser.
What am I missing?
You can follow the below steps to access it from the browser.
Deploy Nginx in your Kubernetes environment by executing the below YAML file.
kubectl create -f {YAML file location}
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deployment
labels:
app: nginx
spec:
replicas: 3
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.14.2
ports:
- containerPort: 80
Execute below nginx-service YAML to access it from the browser.
kubectl create -f {YAML file location}
#Service
#nginx-svc-np.yaml
apiVersion: v1
kind: Service
metadata:
name: nginx-service
labels:
app: nginx
spec:
selector:
app: nginx
type: LoadBalancer
ports:
- port: 80
targetPort: 80
externalIPs:
- 192.168.1.155
Now you can access Nginx from your browser.
http://192.168.1.155/ (Please use your external IP)
I have had the same. But I am running minikube. So, changing minikube driver helped me.

GCP Couldn't reach Kubernetes External Load Balancer IP from outside

I have a cluster created in the GCP cloud having a simple k8s YAML file.
apiVersion: v1
kind: Service
metadata:
name: lb-svc
labels:
app: lb-demo
spec:
type: LoadBalancer
ports:
- port: 8080
selector:
app: np-demo
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: np-deploy
spec:
replicas: 3
selector:
matchLabels:
app: np-demo
template:
metadata:
labels:
app: np-demo
spec:
containers:
- name: np-pod
image: nigelpoulton/k8s-deep-dive:0.1
imagePullPolicy: Always
ports:
- containerPort: 8080
Now; this YAML configuration has a LoadBalancer service which in return exposes an external IP address to the public.
thus we can see the external IP address using:
kubectl get svc
The issue is, I can easily access the load balancer using curl within the cloud shell but couldn't reach it when trying to access it from outside (example browser).
Tried:
curl external-ip:8080
Any help?
Your service ip only accessible to local VPC, if you need to expose service or ingress you need reserve a static ip, read here to reserve a static ip https://cloud.google.com/compute/docs/ip-addresses/reserve-static-external-ip-address
To assign your static ip to service, you need set loadBalancerIP on your service configuration
apiVersion: v1
kind: Service
metadata:
name: lb-svc
labels:
app: lb-demo
spec:
type: LoadBalancer
loadBalancerIP: <your reserved ip>
ports:
- port: 8080
selector:
app: np-demo
To assign your ip to ingress
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: my-ingress
annotations:
kubernetes.io/ingress.global-static-ip-name: <name of reserved static ip>
labels:
app: my-app
spec:
backend:
serviceName: lb-svc
servicePort: 8080
read more here