Api Gateway easy
If your API Gateway is the only entry point for your cluster and it goes offline, what is the consequence for your system status?
- A The microservices will continue to talk to each other, but your external service is completely unreachable (Total Outage).
- B All data in the backend databases will be instantly corrupted beyond repair.
- C The system will switch to a slow backup mode where it emails the users instead of using an API.
- D Only the users who are currently logged in will be affected; new users can still connect.
Answer: A. The microservices will continue to talk to each other, but your external service is completely unreachable (Total Outage).
Because the Gateway is the 'Single Entry Point', it is also a 'Single Point of Failure'. If it fails, even if your backend services are 100% healthy, no one from the outside can reach them. This is why professional setups always run multiple redundant instances of the API Gateway behind a load balancer.
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Get the appRelated questions
- Your Gateway communicates with backends via HTTP/1.1 connections. A slow backend service causes 'Head-of-Line Blocking'. How does switching to HTTP/2 as the Gateway-to-Backend transport mitigate this?
- What is the primary architectural role of an API Gateway in a microservices environment?
- Why is 'Stateless Token Validation' (e.g., using JWTs) significantly more scalable at the Gateway level than 'Stateful Validation' (e.g., using Opaque/Reference Tokens)?
- Your Gateway is configured to cache any URL ending in `.css` or `.jpg`. An attacker tricks a victim into visiting `https://api.com/v1/profile/info/style.css`. How can this lead to an 'Account Takeover'?
- An API is receiving a sudden surge of 10,000 requests per second from a single IP address. How does an API Gateway preserve the stability of the backend services?
- How can an API Gateway help prevent 'Double Charging' in a payment system when a mobile client retries a failed request due to a poor connection?