Tech Story

Cloud / DevOps / SRE / Networking

Every system
has a story.

Animated explainers on how real systems work and how they break. Every video starts with a real problem, then follows the packets until it all makes sense.

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A hand-drawn sketch of a web request You type techstoryexplained.com on your laptop. A small packet character walks the request across the internet to a sleeping server, which wakes up and smiles. The packet walks back carrying the page, and the page loads with 200 OK. techstoryexplained.com you type this Your laptop the internet The server 200 OK GET /

01Chapter one

It starts with a name

Computers do not know names, only addresses. So before your browser can load anything, it asks a resolver one question: where does this name live?

Most of the time the resolver already knows. That cache is why the web feels instant, and why a wrong answer can stick around for an hour.

Watch the full DNS episode

How DNS answers from cache Your laptop sends a query for shop.example.com to the resolver. The resolver finds it in its cache with a time to live of 3600 seconds, a cache hit, and sends back the address 203.0.113.10. shop.example.com api.example.com 198.51.100.7 120s shop.example.com 203.0.113.10 3600s mail.example.com 198.51.100.25 300s RESOLVER CACHE 1 Query CACHE HIT 2 Answer 203.0.113.10 Your laptop Resolver where is shop? 203.0.113.10

02Chapter two

When a server breaks

Servers fail all the time. A load balancer keeps asking each one a simple question: are you OK?

When a server stops answering, traffic quietly goes around it. That is why one broken machine rarely takes a whole site down.

Watch: Load Balancer vs Reverse Proxy

A load balancer routing around a failed server Requests from users go through a load balancer to three servers. Server 2 fails its health check and turns red, so the load balancer sends new requests to servers 1 and 3 instead. health check failed ! Users Load balancer

03Latest videos

Fresh from the channel

All videos on YouTube

04Series

Follow a story from start to finish

05Courses

Free courses are on the way

Step-by-step courses built the same way as the videos: real problems, animated, no shortcuts. The first one is about GitHub Actions.

See what is coming

Every system has a story.

New episodes most weeks. Subscribe so you do not miss the next one.

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