Posted by okchildhood 3 days ago
The biggest pain of DNS for most people is if someone has set the TTL to an absurdly large number, or if a resolver isn't respecting TTL. And once you get into advanced configurations, SOAs and delegation certainly create their own headaches!
One nitpick I had was that the subdomain examples are more likely to be hosts. They could be either, but was not mentioned. Perhaps I missed.