Typical domain knowledge questions look like
- Design Twitter
- Design a URL shortener
The typical system design interview will take up 40 ~ 50 minutes. Depends on the company there are also companies that do “smaller” system design interview, such as using 15 minutes to talk about how circuit breaker works in general.
The key is to mix your learning mode.
Passive Learning Mode: Preparation
You might find a lot of resources on the internet but here, I want to keep it small so that it could help you to begin preparing while doesn’t overload you with a lot of resources that you would never complete. Reading articles and watching videos help, but those are passive learning. In the end, I believe backend system design requires you to be an active learner
For preparation I recommend:
Active Learning Mode: Practice
You can choose to practice with friends. There are a lot of places online to practice, and I recommend pramp since it’s free.