// Module included in the following assemblies:
//
// * serverless/knative-serving/config-custom-domains/create-domain-mapping.adoc

:_mod-docs-content-type: PROCEDURE
[id="serverless-create-domain-mapping_{context}"]
= Creating a custom domain mapping

You can customize the domain for your Knative service by mapping a custom domain name that you own to a Knative service. To map a custom domain name to a custom resource (CR), you must create a `DomainMapping` CR that maps to an Addressable target CR, such as a Knative service or a Knative route.

.Prerequisites

* The {ServerlessOperatorName} and Knative Serving are installed on your cluster.
* Install the OpenShift CLI (`oc`).
* You have created a project or have access to a project with the appropriate roles and permissions to create applications and other workloads in {product-title}.
* You have created a Knative service and control a custom domain that you want to map to that service.
+
[NOTE]
====
Your custom domain must point to the IP address of the {product-title} cluster.
====

.Procedure

. Create a YAML file containing the `DomainMapping` CR in the same namespace as the target CR you want to map to:
+
[source,yaml]
----
apiVersion: serving.knative.dev/v1alpha1
kind: DomainMapping
metadata:
 name: <domain_name> <1>
 namespace: <namespace> <2>
spec:
 ref:
   name: <target_name> <3>
   kind: <target_type> <4>
   apiVersion: serving.knative.dev/v1
----
<1> The custom domain name that you want to map to the target CR.
<2> The namespace of both the `DomainMapping` CR and the target CR.
<3> The name of the target CR to map to the custom domain.
<4> The type of CR being mapped to the custom domain.
+
.Example service domain mapping
[source,yaml]
----
apiVersion: serving.knative.dev/v1alpha1
kind: DomainMapping
metadata:
 name: example-domain
 namespace: default
spec:
 ref:
   name: example-service
   kind: Service
   apiVersion: serving.knative.dev/v1
----
+
.Example route domain mapping
[source,yaml]
----
apiVersion: serving.knative.dev/v1alpha1
kind: DomainMapping
metadata:
 name: example-domain
 namespace: default
spec:
 ref:
   name: example-route
   kind: Route
   apiVersion: serving.knative.dev/v1
----

. Apply the `DomainMapping` CR as a YAML file:
+
[source,terminal]
----
$ oc apply -f <filename>
----