If I create a new AWS Application Load Balancer (ALB) using HTTP, then AWS will create a load balancer with a randomly assigned domain name. Why can't AWS do the same thing when I create a new ALB using HTTPS? Instead, when creating a new ALB using HTTPS, AWS requires me to provide a custom domain name and custom certs.
3 Answers
The reason is that for valid public SSL certificate you require your own domain that you control. You can't register the certificate for the default domain provided by AWS for ALB because this is not your domain.
Having SSL certs is a lot of work, including managing its registration and renewals. I guess AWS does not want to do that, though they provide SSL for CloudFront AWS-provided default domains.
great question... With many other aws tools like Amplify you will get a working https address on random aws domain, without the need to upload a certificate to a custom domain. here They force me to use a certificate, which forces me to use aa custom domain and not the random autogenerated aws https address.
As per the docs - https://docs.aws.amazon.com/elasticloadbalancing/latest/application/create-https-listener.html
To use an HTTPS listener, you must deploy at least one SSL/TLS server certificate on your load balancer. The load balancer uses a server certificate to terminate the front-end connection and then decrypt requests from clients before sending them to the targets.
The load balancer requires X.509 certificates (SSL/TLS server certificates). Certificates are a digital form of identification issued by a certificate authority (CA). A certificate contains identification information, a validity period, a public key, a serial number, and the digital signature of the issuer.
When you create a certificate for use with your load balancer, you must specify a domain name.
You could use Amazon's ACM to provision your certs. You will only be charged for the application as mentioned in the docs below - https://docs.aws.amazon.com/acm/latest/userguide/acm-billing.html
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