Hello! Have you ever experienced a day when Discord, Notion, various news sites, and even stock trading apps suddenly became inaccessible simultaneously? π±
You might think it’s your internet, so you try turning your Wi-Fi off and on, but it’s no use. Often, the culprit is none other than ‘Cloudflare’.
What exactly is this company, and why does a problem with it bring 20% of the world’s internet to a halt? Today, we’ll delve into the influence of Cloudflare, which shakes the internet world, and its operating principles in great detail. π
1. Who Exactly is Cloudflare? (The Internet’s Security Guard π‘οΈ)
When we access websites (like Naver, Google, etc.), we usually think our computer connects directly to the server. However, sites using Cloudflare are different.
- Intermediary (Reverse Proxy): Cloudflare acts as a massive ‘middleman’ and ‘shield’ standing between the user and the real web server.
- Role: It blocks hacker attacks (DDoS) and organizes traffic before sending it to the server.
In other words, it’s a structure where all visitors must pass through the ‘gateway’ of Cloudflare to enter the restaurant (website). But what if this gateway collapses? Even if the restaurant is perfectly fine, visitors won’t be able to enter. π«
2. Why Does Everyone Use It, Magnifying the Problem? (The Convenience Store Effect πͺ)
The reason the internet world has come to rely on Cloudflare is because of the CDN (Content Delivery Network) service they provide.
- Principle: If a Korean user wants to view data from a server in the US, it’s too slow. So, Cloudflare builds ‘data warehouses (Edge Servers)’ all over the world.
- Effect: For Korean users, data is provided from Cloudflare’s warehouse in Korea. It’s incredibly fast! π
The problem is that too many sites (over 20% of websites worldwide) are using Cloudflare due to this convenience. A massive ‘Single Point of Failure’ has been created.
3. The Nightmare of ‘502 Bad Gateway’ π
When Cloudflare goes down, the screen we most often see is “502 Bad Gateway”. The underlying meaning of this error message is as follows:
> “I (Cloudflare) am here, but the connection to the real server behind me is broken (or I’m sick and can’t make the connection).”
Even if the real server (the website’s core) is running perfectly fine, if the Cloudflare server blocking its front goes down, no one can access it. It’s literally like a highway tollgate collapsing, leaving cars unable to move. πππ
4. Holding the Internet’s Address Book (DNS) π
Cloudflare doesn’t just deliver data. When we type an internet address (e.g., https://www.google.com/search?q=google.com), it also provides one of the world’s most used DNS services (1.1.1.1), which converts this into a numerical address (IP) that computers understand.
What if there’s a problem with Cloudflare’s DNS system?
- The site is alive,
- The network is fine,
- But a ridiculous situation occurs where you can’t connect “because the address can’t be found.” π΅βπ«
5. BGP Routing Error: Erasing the Internet’s Map πΊοΈβ
Sometimes Cloudflare engineers make configuration mistakes. (e.g., major outages in 2019, 2020) At such times, the internet routing configuration called BGP (Border Gateway Protocol) gets tangled, which is like deleting all road information from a navigation system worldwide.
Traffic loses its way, circles around, or disappears like a black hole, and at such times, even other services not using Cloudflare are sequentially slowed down.
π Conclusion: The Price of Leaning on Too Big a Giant
Cloudflare is a valuable entity that makes the internet faster and safer. However, like the adage “Don’t put all your eggs in one basket,” it also highlights the danger that the global internet relies too heavily on a single company.
If Cloudflare sneezes, the global internet catches the flu. Next time the internet suddenly goes down, before blaming your Wi-Fi router, check the news first. You might ask, “Is it Cloudflare again?” π
Leave a Reply