**To update a custom domain name** The following ``update-domain-name`` example specifies a new ACM certificate for the ``api.example.com`` custom domain name. :: aws apigatewayv2 update-domain-name \ --domain-name api.example.com \ --domain-name-configurations CertificateArn=arn:aws:acm:us-west-2:123456789012:certificate/123456789012-1234-1234-1234-12345678 Output:: { "ApiMappingSelectionExpression": "$request.basepath", "DomainName": "regional.example.com", "DomainNameConfigurations": [ { "ApiGatewayDomainName": "d-id.execute-api.us-west-2.amazonaws.com", "CertificateArn": "arn:aws:acm:us-west-2:123456789012:certificate/123456789012-1234-1234-1234-12345678", "EndpointType": "REGIONAL", "HostedZoneId": "123456789111", "SecurityPolicy": "TLS_1_2", "DomainNameStatus": "AVAILABLE" } ] } For more information, see `Setting up a regional custom domain name in API Gateway <https://docs.aws.amazon.com/apigateway/latest/developerguide/apigateway-regional-api-custom-domain-create.html>`__ in the *Amazon API Gateway Developer Guide*.