
AWS Certified Advanced Networking – Specialty (ANS-C01) Certification Guide
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It’s not DNS
There’s no way it’s DNS
It was DNS
The above Haiku is a popular internet meme reflecting the truism that Domain Name System (DNS) failures and misconfigurations are the root cause of many application and service outages. DNS is a fundamental building block upon which the internet rests. Why is this so? Can you imagine the need to know the IP address of a website so you can visit it in a web browser? If it’s an IPv4 address, it might be somewhat feasible, but what about an IPv6 address that is 16 bytes long? For example, to reach the Trailcats website using the bare IP address, you would have to input 192.0.2.1
for IPv4 or 2001:db8:f000:g000:3333:4444:5555:ff11
for IPv6. The DNS is the translation layer of numbers to names, making the Internet accessible to humans.
The DNS is an essential underlying technology, and its misconfiguration represents a frequent cause of outages. This is because DNS configurations...