Difference between Horizontal Scalability vs Vertical Scaling in System Design and Microservices

Hello folks , one question which I have been asked repeatedly on many System design and Java Developer interviews are how do you scale your system? In particular how do you scale your Microservices?

This is a great question to ask any experienced developers because its open ended and its gives an opportunity to candidate to express themselves and also interviewers to know more about their knowledge, experience, and thought process.

Thanks to my habit of reading blogs and articles, I feel I am little bit more familiar with new concepts and terms compared to my competition.

So, when I was first asked this question on senior Java developer role and I mentioned that there are two ways to scale your application either horizontally or vertically then the interviewer was really impressed because he himself have never heard about the term, even though he may be familiar with the concept and process.

Now, you can say that I got lucky which is true but I was able to make an impression because I read blogs and articles and I can use buzz words and demonstrate that I understand them.

In this article, I will tell you the exact difference between horizontal and vertical scaling and when to use…