# Lambda architecture
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If you’ve deployed the Lambda architecture stack and have set the Use Existing CloudFront Distribution template parameter to Yes, use the following instructions to complete your setup.

## Setting the Origin
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1. In the CloudFront console, navigate to the distribution you indicated in the Existing CloudFront Distribution ID template parameter.

1. Select the Origins tab and click **Create origin**.

1. Set the Origin domain as the API Gateway execution link. This value can be found by placing the Physical ID of the stack’s AWS::ApiGateway::RestApi in the search field and selecting LambdaRestApi under API Gateway.

1. Set the Origin path to `/image`.

1. Select **Create origin**.

## Setting the behavior
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1. In the CloudFront console, navigate to the distribution you indicated in the Existing CloudFront Distribution ID template parameter.

1. Select the Behaviors tab and choose **Create behavior** 

1. Set the Path pattern you’d like to point to your solution instance, in a Solution created distribution, this is Default (\$1)

1. Set the Origin to the Origin created in the previous section.

1. Set the Viewer Protocol policy to `Redirect HTTP to HTTPS` 

1. Set the Cache Policy to the one named `ServerlessImageHandler-${UUID}`.

1. Set the Origin request policy to the one named `ServerlessImageHandler-${UUID}`.

1. Set the Viewer request Function type to CloudFront Functions, and the Function ARN to the one named `sih-apig-request-modifier-${UUID}`.

1. Select **Create behavior**.