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---
---
{% capture overview %}
This page shows how to create a Kubernetes Service object to that provides
load-balanced access to an application running in a cluster.
{% endcapture %}
{% capture prerequisites %}
* Install [kubectl](http://kubernetes.io/docs/user-guide/prereqs).
* Create a Kubernetes cluster, including a running Kubernetes
API server. One way to create a new cluster is to use
[Minikube](/docs/getting-started-guides/minikube).
* Configure `kubectl` to communicate with your Kubernetes API server. This
configuration is done automatically if you use Minikube.
{% endcapture %}
{% capture objectives %}
* Run two instances of a Hello World application
* Create a Service object
* Use the Service object to access the running application
{% endcapture %}
{% capture lessoncontent %}
### Creating a Service for an application running in two pods
1. Run a Hello World application in your cluster:
kubectl run hello-world --replicas=2 --labels="run=load-balancer-example" --image=gcr.io/google-samples/node-hello:1.0 --port=8080
1. List the pods that are running the Hello World application:
kubectl get pods --selector="run=load-balancer-example"
The output is similar to this:
NAME READY STATUS RESTARTS AGE
hello-world-2189936611-8fyp0 1/1 Running 0 6m
hello-world-2189936611-9isq8 1/1 Running 0 6m
1. List the replica set for the two Hello World pods:
kubectl get replicasets --selector="run=load-balancer-example"
The output is similar to this:
NAME DESIRED CURRENT AGE
hello-world-2189936611 2 2 12m
1. Create a Serivice object that exposes the replica set:
kubectl expose rs <your-replica-set-name> --type="LoadBalancer" --name="example-service"
where `<your-replica-set-name>` is the name of your replica set.
1. Display the IP addresses for your service:
kubectl get services example-service
The output shows the internal IP address and the external IP address of
your service. If the external IP address shows as `<pending>`, repeat the
command.
Note: If you are using Minikube, you don't get an external IP address. The
external IP address remains in the pending state.
NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE
example-service 10.0.0.160 <pending> 8080/TCP 40s
1. Use your Service object to access the Hello World application:
curl <your-external-ip-address>:8080
where `<your-external-ip-address>` is the external IP address of your
service.
The output is a hello message from the application:
Hello Kubernetes!
Note: If you are using Minikube, enter these commands:
kubectl cluster-info
kubectl describe services example-service
The output displays the IP address of your Minikube node and the NodePort
value for your service. Then enter this command to access the Hello World
application:
curl <minikube-node-ip-address>:<service-node-port>
where `<minikube-node-ip-address>` us the IP address of your Minikube node,
and `<service-node-port>` is the NodePort value for your service.
### Using a service configuration file
As an alternative to using `kubectl expose`, you can use a
[service configuration file](/docs/user-guide/services/operations)
to create a Service.
{% endcapture %}
{% capture cleanup %}
If you want to stop the Hello World application, enter these commands:
TODO
{% endcapture %}
{% capture whatsnext %}
Learn more about
[connecting applications with services](/docs/user-guide/connecting-applications/).
{% endcapture %}
{% include templates/tutorial.md %}