Still happening in 2021 on an EC2 single machine deployment (10.8.1), server federated with portal. I detailed in another reply but we have 1 signed cert (not wildcard) for our domain. The default self-signed certs for Portal/Server are still active and our internal browser's do not recognize our machine name/localhost as secure, but our domain is secured.
Are any of these solutions Esri supported? I assume everyone with an EC2 will have to do something for this issue? Support mentioned to add an SAN with the amazon domain, like (slides 23-25), but that is not an option since it is blacklisted. Support said it is out of their scope, yet our Enterprise won't function properly until this is resolved. (so how is it out of scope?)