No, this isn't domain fronting. This has to do with PTR records, reverse DNS. Domain fronting is all about the forward lookups, normally you wouldn't be makin

No, this isn't domain fronting. This has to do with PTR records, reverse DNS. Domain fronting is all about the forward lookups, normally you wouldn't be making PTR requests in a normal web request. Putting all your infrastructure under a single utility domain is very common, all the ISPs do it. It's good practice for reasons listed elsewhere in here. Bringing in the practice of domain fronting into this conversation is technically irrelevant, but it does advance an agenda, relying upon the less-than-technically literate HN audience from being confused between reverse DNS, domain fronting, and firewall rules.