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One note about the last highlighted field in the screenshot (Custom SSL certificate) - this is where the SSL cert for the custom domain appears if it was properly configured in ACM in Step 2. Although we have not selected anything in the screenshot (because we do not have SSL cert for our example domain), this field cannot be left empty - it must be set.
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Step 3a - Create DNS record for your custom domain
Each CloudFront distribution has a unique domain name generated by AWS when the distribution is created. Create a CNAME record in your DNS provider, that points your custom domain at the unique hostname for your CloudFront distribution.
Example record:Record name
Name: app.mycustomdomain.com
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Type: CNAME
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Value: unique domain name generated by CloudFront
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After creating the DNS record, allow at least 1 min for DNS to propagate and then verify if the record has been created properly using one of many DNS lookup tools like https://www.whatsmydns.net/ .
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