They sent me an assignment to complete within 10 days. I submitted it and after that did not hear any feedback for a long time. Then I decided to send an email to the hiring manager, and after 3 days, they sent a message that they want to schedule my interview with the hiring manager.

I confirmed my availability for the suggested time. No one showed up for the interview, even after waiting for 30 minutes. It was super unprofessional, and I was not expecting such a thing with Cloudflare.

Later, they said that the hiring manager was not available, so they fixed an interview with another person from the team instead.

That interview went well. We had a good talk and discussed many things. I answered all the questions to the best of my knowledge, and I felt that the person had a positive opinion of me. But just the next day, I got rejected straight away for the role. I don't think they even checked my interview feedback internally; they just rejected.

Overall, a very negative experience, very unprofessional.

Describe in detail how DNS works.