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‎modules/virt-creating-a-service-from-a-virtual-machine.adoc‎

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// Module included in the following assemblies:
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//
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// * virt/virtual_machines/vm_networking/virt-using-the-default-pod-network-with-virt.adoc
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[id="virt-creating-a-service-from-a-virtual-machine_{context}"]
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= Creating a service from a virtual machine
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Create a service from a running virtual machine by first creating a `Service` object to expose the virtual machine.
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The `ClusterIP` service type exposes the virtual machine internally, within the cluster. The `NodePort` or `LoadBalancer` service types expose the virtual machine externally, outside of the cluster.
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This procedure presents an example of how to create, connect to, and expose a `Service` object of `type: ClusterIP` as a virtual machine-backed service.
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[NOTE]
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====
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`ClusterIP` is the default service `type`, if the service `type` is not specified.
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====
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.Procedure
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. Edit the virtual machine YAML as follows:
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+
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[source,yaml]
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----
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apiVersion: kubevirt.io/v1alpha3
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kind: VirtualMachine
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metadata:
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name: vm-ephemeral
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namespace: example-namespace
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spec:
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running: false
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template:
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metadata:
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labels:
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special: key <1>
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spec:
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domain:
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devices:
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disks:
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- name: containerdisk
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disk:
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bus: virtio
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- name: cloudinitdisk
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disk:
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bus: virtio
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interfaces:
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- masquerade: {}
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name: default
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resources:
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requests:
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memory: 1024M
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networks:
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- name: default
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pod: {}
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volumes:
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- name: containerdisk
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containerDisk:
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image: kubevirt/fedora-cloud-container-disk-demo
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- name: cloudinitdisk
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cloudInitNoCloud:
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userData: |
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#!/bin/bash
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echo "fedora" | passwd fedora --stdin
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----
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<1> Add the label `special: key` in the `spec.template.metadata.labels` section.
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+
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[NOTE]
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====
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Labels on a virtual machine are passed through to the pod. The labels on
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the `VirtualMachine`, for example `special: key`, must match the labels in
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the `Service` YAML `selector` attribute, which you create later
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in this procedure.
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====
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. Save the virtual machine YAML to apply your changes.
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. Edit the `Service` YAML to configure the settings necessary to create and expose the `Service` object:
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[source,yaml]
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----
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apiVersion: v1
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kind: Service
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metadata:
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name: vmservice <1>
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namespace: example-namespace <2>
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spec:
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ports:
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- port: 27017
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protocol: TCP
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targetPort: 22 <3>
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selector:
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special: key <4>
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type: ClusterIP <5>
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----
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<1> Specify the `name` of the service you are creating and exposing.
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<2> Specify `namespace` in the `metadata` section of the `Service` YAML that corresponds to the `namespace` you specify in the virtual machine YAML.
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<3> Add `targetPort: 22`, exposing the service on SSH port `22`.
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<4> In the `spec` section of the `Service` YAML, add `special: key` to the `selector` attribute, which corresponds to the `labels` you added in the virtual machine YAML configuration file.
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<5> In the `spec` section of the `Service` YAML, add `type: ClusterIP` for a
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ClusterIP service. To create and expose other types of services externally, outside of the cluster, such as `NodePort` and `LoadBalancer`, replace
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`type: ClusterIP` with `type: NodePort` or `type: LoadBalancer`, as appropriate.
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. Save the `Service` YAML to store the service configuration.
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. Create the `ClusterIP` service:
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[source,terminal]
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----
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$ oc create -f <service_name>.yaml
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----
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. Start the virtual machine. If the virtual machine is already running, restart it.
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. Query the `Service` object to verify it is available and is configured with type `ClusterIP`.
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.Verification steps
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* Run the `oc get service` command, specifying the `namespace` that you reference in the virtual machine and `Service` YAML files.
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[source, terminal]
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----
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$ oc get service -n example-namespace
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----
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.Example output
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[source, terminal]
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----
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NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
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vmservice ClusterIP 172.30.3.149 <none> 27017/TCP 2m
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----
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** As shown from the output, `vmservice` is running.
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** The `TYPE` displays as `ClusterIP`, as you specified in the `Service` YAML.
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. Establish a connection to the virtual machine that you want to use to back your service. Connect from an object inside the cluster, such as another virtual machine.
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.. Edit the virtual machine YAML as follows:
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[source,yaml]
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----
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apiVersion: kubevirt.io/v1alpha3
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kind: VirtualMachine
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metadata:
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name: vm-connect
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namespace: example-namespace
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spec:
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running: false
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template:
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spec:
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domain:
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devices:
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disks:
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- name: containerdisk
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disk:
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bus: virtio
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- name: cloudinitdisk
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disk:
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bus: virtio
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interfaces:
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- masquerade: {}
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name: default
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resources:
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requests:
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memory: 1024M
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networks:
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- name: default
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pod: {}
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volumes:
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- name: containerdisk
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containerDisk:
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image: kubevirt/fedora-cloud-container-disk-demo
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- name: cloudinitdisk
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cloudInitNoCloud:
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userData: |
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#!/bin/bash
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echo "fedora" | passwd fedora --stdin
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----
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.. Run the `oc create` command to create a second virtual machine, where `file.yaml` is the name of the virtual machine YAML:
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[source,terminal]
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----
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$ oc create -f <file.yaml>
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----
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.. Start the virtual machine.
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.. Connect to the virtual machine by running the following `virtctl` command:
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[source,terminal]
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----
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$ virtctl -n example-namespace console <new-vm-name>
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----
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[NOTE]
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====
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For service type `LoadBalancer`, use the `vinagre` client to connect your
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virtual machine by using the public IP and port.
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External ports are dynamically allocated when using service type
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`LoadBalancer`.
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====
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.. Run the `ssh` command to authenticate the connection, where `172.30.3.149` is the ClusterIP of the service and `fedora` is the user name of the virtual machine:
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[source,terminal]
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----
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$ ssh fedora@172.30.3.149 -p 27017
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----
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.Verification steps
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* You receive the command prompt of the virtual machine backing the service you want to expose. You now have a service backed by a running virtual machine.

‎virt/virtual_machines/vm_networking/virt-using-the-default-pod-network-with-virt.adoc‎

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include::modules/virt-template-vm-config.adoc[leveloffset=+2]
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include::modules/virt-template-windows-vmi.adoc[leveloffset=+2]
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include::modules/virt-creating-a-service-from-a-virtual-machine.adoc[leveloffset=+1]
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.Additional resources
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* xref:../../../networking/configuring_ingress_cluster_traffic/configuring-externalip.adoc#configuring-externalip[Configuring external IPs]

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