I have created small nginx deployment and type as LoadBalancer in Azure Kubernetes service, but I was unable to access the application using LoadBalaner service. Can some one provide the solution
I have already updated security group to allow all traffic, but no use.
Do I need to update any security group to access the application?
Please find the deployment file.
cat nginx.yml
apiVersion: v1
kind: Service
metadata:
name: nginx-kubernetes
spec:
type: LoadBalancer
ports:
- port: 8080
targetPort: 8080
selector:
app: hello-kubernetes
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-kubernetes
spec:
replicas: 3
selector:
matchLabels:
app: hello-kubernetes
template:
metadata:
labels:
app: hello-kubernetes
spec:
containers:
- name: hello-kubernetes
image: nginx:latest
ports:
- containerPort: 8080
Nginx container is using port 80 by default and you are trying to connect to port 8080 where nothing is listening and thus getting connection refused.
Take a look here at nginx conateiner Dockerfile. What port do you see?
All you need to do to make it work is to change target port like following:
apiVersion: v1
kind: Service
metadata:
name: nginx-kubernetes
spec:
ports:
- port: 8080
targetPort: 80
selector:
app: hello-kubernetes
Additionally it would be nice to change containerPort as following:
spec:
containers:
- name: hello-kubernetes
image: nginx:latest
ports:
- containerPort: 80
Related
I created a Digitalocean kubernetes cluster and create a service with 4 replicas. the service type is LoadBalancer. the load balancer is also created. but I posted my request to the target endpoint by using postman. and I have written the endpoint with the pod host name. but every time I get the response from the same pod. if the load is balanced by the load balancer, the requests should go to each and every pods. but is not happening as I expected.
my manifest file like below.
apiVersion: apps/v1
kind: Deployment
metadata:
name: user-service-deployment
labels:
app: user-service
spec:
replicas: 3
selector:
matchLabels:
app: user-service
template:
metadata:
labels:
app: user-service
spec:
containers:
- name: user-service
image: myRepo/ms-user-service:1.0.1
ports:
- containerPort: 8080
env:
- name: SPRING_PROFILES_ACTIVE
value: proud
- name: MY_NODE_NAME
valueFrom:
fieldRef:
fieldPath: spec.nodeName
---
apiVersion: v1
kind: Service
metadata:
name: user-service
spec:
selector:
app: user-service
type: LoadBalancer
ports:
- protocol: TCP
port: 8080
targetPort: 8080
please resolve this problem.
you have to disable the keepalive feature (service.beta.kubernetes.io/do-loadbalancer-enable-backend-keepalive) when you create the service. under the metadata.annotations you can configure it like the below. read for more detail.
apiVersion: v1
kind: Service
metadata:
name: user-service
annotations:
service.beta.kubernetes.io/do-loadbalancer-enable-backend-keepalive: "false"
spec:
selector:
app: user-service
type: LoadBalancer
ports:
- protocol: TCP
port: 8080
targetPort: 8080
This is about Traefik not about the way it works with K3s Kubernetes generally, so please don't give me a general K8s answer.
I have a simple k3s deployment and service that looks like this...
apiVersion: v1
kind: Service
metadata:
labels:
app: hello-express
name: app-tier
spec:
type: LoadBalancer
ports:
- protocol: TCP
port: 3000
targetPort: 3000
selector:
tier: app
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: hello-express-deployment
labels:
app: hello-express
tier: app
spec:
replicas: 1
selector:
matchLabels:
tier: app
template:
metadata:
labels:
app: hello-express
tier: app
spec:
containers:
- name: server
image: partyk1d24/hello-express:latest
ports:
- containerPort: 3000
I can then access the application using the external ip and port 3000. Now I would like to change that port from 3000 to 80. Apparently this is controlled locally on K3s using Traefik. I tried the following while looking here...
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: hello-express-ingress
annotations:
kubernetes.io/ingress.class: "traefik"
spec:
rules:
- http:
paths:
- path: /
pathType: Prefix
backend:
service:
name: app-tier
port:
number: 80
But when I try to go to the site I get...
curl 192.168.X.XXX
Service Unavailable%
The Blog is a little old so I am sure I am doing something wrong can someone help me identify it?
You should change the port of service to 80.
ports:
- protocol: TCP
port: 80
targetPort: 3000
Keep the target port as 3000.
my deployment yaml:
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deployment
labels:
app: nginx
spec:
selector:
matchLabels:
app: nginx
replicas: 3
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.7.9
ports:
- containerPort: 80
my service yaml:
apiVersion: v1
kind: Service
metadata:
name: nginx-service
spec:
selector:
app: nginx
ports:
- protocol: TCP
port: 80
targetPort: 80
enter image description here
enter image description here
and then I curl 10.104.239.140, but get an error curl: (7) Failed connect to 10.104.239.140:80; Connection timed out
Who can tell me what's wrong?
welcome to SO. That service you've deployed is of type ClusterIP which means it can only be accessed from within the cluster. In your case, it seems you're trying to access it from outside the cluster and thus the connection timed out.
What you can do is, deploy a service of type NodePort or LoadBalancer to access it from outside the cluster. You can read more about different service types here.
You're service would end up something like this:
apiVersion: v1
kind: Service
metadata:
name: nginx-service
spec:
type: NodePort ## or LoadBalancer(supported by Cloud providers like AWS)
selector:
app: nginx
ports:
- protocol: TCP
port: 80
targetPort: 80
# Optional field
# By default and for convenience, the Kubernetes control plane will allocate a port from a range (default: 30000-32767)
nodePort: 30001
I have a very simple web app based on HTML, javascript + little bit jquery, angularjs. It is tested locally on eclipse Jee and on Tomcat and working fine. And its image is working fine on docker locally.
I can access on browser using localhost:8080/xxxx, 127.0.0.1:8080/xxxx, 0.0.0.0:8080. But when I deploy to google Kubernetes, I'm getting "This site can not be reached" if I use the external IP on the browser. I can ping my external IP, but curl is not working. It's not a firewall issue because sample voting app from dockerhub is working fine on my Kubernetes.
my Dockerfile:
FROM tomcat:9.0
ADD GeoWebv3.war /usr/local/tomcat/webapps/GeoWeb.war
expose 8080
my pod yaml
apiVersion: v1
kind: Pod
metadata:
name: front-app-pod
labels:
name: front-app-pod
app: demo-geo-app
spec:
containers:
- name: front-app
image: myrepo/mywebapp:v2
ports:
- containerPort: 80
my service yaml
apiVersion: v1
kind: Service
metadata:
name: front-service
labels:
name: front-service
app: demo-geo-app
spec:
type: LoadBalancer
ports:
- port: 80
targetPort: 80
selector:
name: front-app-pod
app: demo-geo-app
Change your yamls like this
apiVersion: v1
kind: Service
metadata:
name: front-service
labels:
name: front-service
app: demo-geo-app
spec:
type: LoadBalancer
ports:
- port: 80
targetPort: 8080
selector:
name: front-app-pod
app: demo-geo-app
apiVersion: v1
kind: Pod
metadata:
name: front-app-pod
labels:
name: front-app-pod
app: demo-geo-app
spec:
containers:
- name: front-app
image: myrepo/mywebapp:v2
ports:
- containerPort: 8080
You expose the port 8080 in the docker image. Hence in the service you have to say that the targetPort: 8080 to redirect the traffic coming to load balancer on port 80 to the container's port 8080
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.
This is the file Dockerfile of lucky-word-server:
FROM frolvlad/alpine-oraclejdk8
ADD build/libs/common-config-server-0.0.1-SNAPSHOT.jar common-config-server.jar
EXPOSE 8888
ENTRYPOINT ["/usr/bin/java", "-Xmx128m", "-Xms128m"]
CMD ["-jar", "common-config-server.jar"]
This is the file Dockerfile of lucky-word-client:
FROM frolvlad/alpine-oraclejdk8
ADD build/libs/lucky-word-client-0.0.1-SNAPSHOT.jar lucky-word-client.jar
EXPOSE 8080
ENTRYPOINT ["/usr/bin/java", "-Xmx128m", "-Xms128m"]
CMD ["-jar", "-Dspring.profiles.active=italian", "lucky-word-client.jar"]
This is deployment of lucky-word-server:
apiVersion: apps/v1
kind: Deployment
metadata:
name: lucky-server
spec:
selector:
matchLabels:
app: lucky-server
replicas: 1
template:
metadata:
labels:
app: lucky-server
spec:
containers:
- name: lucky-server
image: lucky-server-img
imagePullPolicy: Never
ports:
- containerPort: 8888
This is the service of lucky-word-server:
kind: Service
apiVersion: v1
metadata:
name: lucky-server
spec:
selector:
app: lucky-server
ports:
- protocol: TCP
port: 8888
type: NodePort
This is the deployment of lucky-word-client:
apiVersion: apps/v1
kind: Deployment
metadata:
name: lucky-client
spec:
selector:
matchLabels:
app: lucky-client
replicas: 1
template:
metadata:
labels:
app: lucky-client
spec:
containers:
- name: lucky-client
image: lucky-client-img
imagePullPolicy: Never
ports:
- containerPort: 8080
This is the service of lucky-word-client:
kind: Service
apiVersion: v1
metadata:
name: lucky-client
spec:
selector:
app: lucky-client
ports:
- protocol: TCP
port: 8080
type: NodePort
As #suren stated you should specify the target port in the service definition.
And you should change the endpoint URL of the server that client calls to reflect minikube_host_ip. There are couple of ways to achieve that. The naive method would be as follows.
Change your Kubernetes service for the server to have a static Nodeport as follows:
kind: Service
apiVersion: v1
metadata:
name: lucky-server
spec:
selector:
app: lucky-server
ports:
- protocol: TCP
port: 8080
nodePort: 32002
type: NodePort
And in your client code just change the endpoint of the server as follows:
http://{minikube_host_ip}:32002 Replace your {minikube_host_ip} with the ip address of the minikube host here.
But if you don't want to hard code the minikube ip you can inject it as an environment variable in your Kuberenetes deployment script. And that environment variable should be captured in your docker file.
Your services are sending the requests to port 80 now. You need to specify parameter targetPort. Should look like this:
kind: Service
apiVersion: v1
metadata:
name: lucky-server
spec:
selector:
app: lucky-server
ports:
- protocol: TCP
targetPort: 8888 #this is your container port. where to send the requests
port: 8888 #this is the service port. it is running on svc-ip:8888
type: NodePort
You should do the same with the other service. Also check the service port. Now it is on 8080 and 8888. You might be hitting them on port 80.
There might be more issues, but for now, these for sure cause a problem.