# Service: kubectl expose Another way to create a service is by using `kubectl expose` command. ```bash kubectl expose

--port= --target-port= --type= ``` * ``: Type of Kubernetes resource (**pod**, **deployment**, **replicaset**, etc.). * ``: Name of the resource to expose. * `--port`: The external port to expose. * `--target-port`: The port on the container to forward traffic to. * `--type`: Type of service (ClusterIP, NodePort, LoadBalancer, or ExternalName). * `--name`: Name of newly created service. ## Expose as ClusterIP Service First lets create a simple deployment object using `nginx` image with name `my-server`. ```bash ➜ kubectl create deployment my-server --image=nginx deployment.apps/my-server created ``` ```bash ➜ kubectl get deployments.apps NAME READY UP-TO-DATE AVAILABLE AGE my-server 1/1 1 0 10s postgres 1/1 1 1 25h simple-go 3/3 3 3 25h ``` Then lets create a service with type `ClusterIP` using `kubectl exec` command. Since `ClusterIP` is the default type we don't need to specify the `--type` argument. ```bash ➜ kubectl expose deployment my-server --port=80 --target-port=80 service/my-server exposed ``` ```bash ➜ kubectl get svc my-server NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE my-server ClusterIP 10.97.240.5 80/TCP 1m2s ``` As we can see above the command will create a service name `my-server` that exposes deployment named `my-server`. We also can get the details in `yaml` format using command `kubectl get service my-server -o yaml`. ```yaml apiVersion: v1 kind: Service metadata: creationTimestamp: "2025-02-10T06:03:41Z" labels: app: my-server name: my-server namespace: default resourceVersion: "129776" uid: 618624cb-2f7e-466e-992d-ecfaf400fb72 spec: clusterIP: 10.97.240.5 clusterIPs: - 10.97.240.5 internalTrafficPolicy: Cluster ipFamilies: - IPv4 ipFamilyPolicy: SingleStack ports: - port: 80 protocol: TCP targetPort: 80 selector: app: my-server sessionAffinity: None type: ClusterIP status: loadBalancer: {} ``` ## Expose as NodePort Service Lets delete our previous service and then expose our deployment again as `NodePort` service. We need to delete the previous service because the expose command by default will name the service same as deployment name. ```bash ➜ kubectl delete svc my-server service "my-server" deleted ``` Because `NodePort` is not the default service type, we need to explicitly specify the service type using `--type` in expose command. ```bash ➜ kubectl expose deployment my-server --type=NodePort --port=80 --target-port=80 service/my-server exposed ``` ```bash ➜ kubectl get svc my-server NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE my-server NodePort 10.100.253.32 80:31775/TCP 8s ``` Now it exposed as `NodePort` and you can try to access it using the minikube IP and the service PORT. But if you use minikube on Mac using docker driver like me you will need `minikube service` to expose it. ## Expose as LoadBalancer Service No lets create another service but with type `LoadBalancer`. This time we explicitly specify the service name using `--name` argument. This command below will create a service with type `LoadBalancer` and name `my-server-lb`. ```bash ➜ kubectl expose deployment my-server --type=LoadBalancer --name=my-server-lb --port=80 --target-port=80 service/my-server-lb exposed ``` ```bash ➜ kubectl get svc my-server-lb NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE my-server-lb LoadBalancer 10.96.60.45 80:30309/TCP 59s ``` Run `minikube tunnel` on the other terminal and test it using curl. ```html ➜ curl http://localhost Welcome to nginx!

Welcome to nginx!

If you see this page, the nginx web server is successfully installed and working. Further configuration is required.

For online documentation and support please refer to nginx.org.
Commercial support is available at nginx.com.

Thank you for using nginx.

``` ## Expose Pod Directly We can also directly expose a pod but this is not recommended in production. For example lets expose the `my-server` pod. ```bash ➜ kubectl get pods NAME READY STATUS RESTARTS AGE my-server-78b5bb4ccc-7cbxf 1/1 Running 0 31m postgres-f8f589d5b-59rw8 1/1 Running 0 25h simple-go-5dc4557ffc-c24fp 1/1 Running 0 25h simple-go-5dc4557ffc-d6tz6 1/1 Running 0 25h simple-go-5dc4557ffc-gv4fv 1/1 Running 0 25h ``` ```bash ➜ kubectl expose pod my-server-78b5bb4ccc-7cbxf --port=80 --target-port=80 service/my-server-78b5bb4ccc-7cbxf exposed ``` The command above will create a `ClusterIP` service that expose the pod `my-server-78b5bb4ccc-7cbxf`. This is not recommended because as we can see below this service is tied to a specific pod. So if that pod is replaced or upgraded, the service will not work. ```bash ➜ kubectl get svc my-server-78b5bb4ccc-7cbxf -o yaml ``` ```yaml apiVersion: v1 kind: Service metadata: creationTimestamp: "2025-02-10T06:34:09Z" labels: app: my-server pod-template-hash: 78b5bb4ccc name: my-server-78b5bb4ccc-7cbxf namespace: default resourceVersion: "131264" uid: 98ef311b-0054-4023-8d83-ca5b0bc9c025 spec: clusterIP: 10.99.77.89 clusterIPs: - 10.99.77.89 internalTrafficPolicy: Cluster ipFamilies: - IPv4 ipFamilyPolicy: SingleStack ports: - port: 80 protocol: TCP targetPort: 80 selector: app: my-server pod-template-hash: 78b5bb4ccc sessionAffinity: None type: ClusterIP status: loadBalancer: {} ``` ## References * --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://bagus-cahyono.gitbook.io/programming-notes/cka/05_service_expose.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.