Microservices Interview Questions With Answers

Introduction

Do you want to crack interviews with Microservices related questions? Do you want to build your career in this industry? First, you’d need to understand its meaning, then you will be able to crack your Microservices Job Interview. In computer networks, a microservices architecture refers to organizing computer systems into services that are scalable. In software development, microservices are widely adopted.

Therefore, in this article, you will figure out the most frequently asked questions in a microservices interview so that you can secure a front-end developer job. Let’s get started!

Questions For Microservices Interview With Answers

1. How Do You Define Microservices?

Generally, a microservices architecture is a set of small, independent services that are related to a business domain. In simple words, it is a self-contained process that always has different and unique business capabilities. These microservice frameworks were designed to solve problems like data search, logging function, or the web service function like hosting web components. Each service is not deployed on another service.

2. What Are the Main Features of Microservice?

Small Focused: The purpose of microservices architecture is simply so that it can be rewritten and maintained by the development team without any extra effort.

Loosely Coupled: Microservices are independent of each other and they don't even need to be coded, this makes development as well as deployment really quick.

Decentralized Governance: Developers can choose the right tools for solving their particular problem.

Language Neutral: You can use any programming language, microservice does not affect other services. For example, some services may be written in Python for faster allocation in the application and some may be written in Java due to its speed and extensive libraries.

3. Main Components of Microservice

There are 5 core components of the Microservices are Orchestration, Containerization, Continuous Deployment, Monitoring And Alerting, Microservices, And DevOps.

4. Write the difference between Monolithic, SOA, and Microservices Architecture.

Monolithic Architecture is like a big container for the design of a software program. In this container, all the software components and the associated components of an application are bundled together tightly.

Service-oriented architecture is a group of services or a style of software design where services are communicating with each other.

Microservice Architecture is an architectural way that affects structuring an application as a cluster of services. It is highly maintainable, testable, independently deployable, loosely coupled, etc. and it's all autonomous services organized around a business domain.

5. Explain spring cloud and spring boot

Spring Cloud: It is a framework for building applications quickly in microservice. This framework helps developers to build both microservice and cloud-based applications. This system can integrate with external systems and contributes significantly to microservice. Follow this diagram to know more

Spring-Boot Microservice: it is an open-source, Java-based architecture that provides its developers to build small, self-contained, ready-to-run applications. This framework helps to develop applications quickly.

6. What is the role of an actuator in spring boot?

Spring boot Actuator is primarily used to provide web services to access the current state of a running application - health, metrics, info, dump, env, etc. Also, this helps to monitor applications in a production environment without configuring any of the spring boot applications.

7. Explain how you can override the default properties of Spring boot projects

After specifying new properties in the application.properties file we can override the internal properties of a spring boot project. For Example: In the spring boot project, you need to add a prefix and suffix in the application.properties file. So, add below listed properties in the file

For prefix – spring.mvc.view.prefix: /WEB-INF/ For suffix – spring.mvc.view.suffix: .jsp

8. What issues are generally solved by spring clouds?

The Spring cloud helped to solved below listed problem

• Complicated issues due to distributed systems like latency overhead, bandwidth issues, security issues, network issues, latency problems, etc.

• Redundancy issues: This issue occurs in distributed systems.

• Load Balancing issues: Optimize the distribution of load between multiple computing resources including central processing units, network links, computer cluster, CPU, etc.

• Various operational overheads can be caused by reduced performance issues.

9. Write the fundamental characteristics of Microservice Design

• Services can be divided based on business capabilities.

• A product, not a project should belong to the team that handles it.

• The development team has the responsibility of any software called Decentralized Governance

• With Microservice you can separately manage each service.

• Microservice provides an automated infrastructure that can be deployed independently.

• Microservice can increase the tolerance for failure of services.

10. Describe the communication between independent microservices.

Microservices interact by HTTP, AMQP, or some binary protocols RTP, TCP, IP. If you would like to automate your entire backend, you can also use Backend as a Service like Space Cloud.

11. What are the benefits of microservice?

Offering better scalability and faster deployment or debugging are the major advantages of the Microservices and provide flexibility and their infrastructure is easy to use with Docker.

12. Describe how Microservices Architecture works.

The purpose of the Microservices Architecture is to develop cloud applications. It consists of a variety of components like API Gateway, Identifier Provider, CDN, Static, etc.

13. What is the use of PACT in Microservices architecture?

Basically, PACT is the open sourced tool that helps to test and increases the reliability of the microservices integration testing. You can test by using some programing language like Java, JavaScript & Scala.

14. Explain CDC

As its name suggests, a Consumer-driven contract is basically a pattern for developing a microservice. It established a contract between the service provider and consumer regarding the format of the data exchanged.

15. What do you mean by Bounded Context?

Bounded contexts are one of the key concepts in the Domain Driven Design (DDD) architectural style, which is increasingly being adopted in the microservices world. Bounded contexts are one of the most critical concepts in microservices architecture because they help separate concerns, resulting in cleaner code and maintaining the applications overall. It is the strategy pattern to deal with large domain models and systems. This question may be asked in your microservices interviews.

16. What are the challenges that one has to face while using Microservices?

In microservices interviews, your interviewer asks questions such as what problems did you face while using microservices. So if you operate microservices then you will face some problems like it demands heavy infrastructure configuration, it requires huge capital to set up microservices. It was also difficult to handle all the components in different environments.

17. What do you mean by Domain-driven design?

Domain-driven design is the favored question of interviews in microservices interviews. In software development, domain-driven design is well respected in the architect's community. So when you develop any software for any business your focus should not be on that technology rather than your focus on the business. I will try to explain in simple terms that if you design any software, your structure of language should be focused on the nature of business and this is called Domain-driven design.

18. How do you define Distributed Transaction?

Due to the number of moving parts involved, transactions are distributed to several services for completion. But many developers face some scalability issues and with it and due to complexities it proves to be an outdated approach in a microservices architecture.

19. Explain Idempotence?

If you sit in the microservices interview then you must face this question. The idea of idempotency is that a request can be repeated endlessly without having side effects on the backend. It is a very common problem in computer science and especially in microservices architecture.

20. What types of microservices tests are used most often?

In computer science, the testing of microservices is relatively complicated. So basically, tests are categorized into 3 categories like bottom level, middle level, and top level test. We can consider the bottom level test is dedicated to technology that is a completely automated test. Then, a mid-level test deals with the exploratory test that can figure out some stress and usability test. Lastly, the top-level test is the acceptance test. Acknowledging the software's capabilities is the purpose of the acceptance tests.

21. Describe how containers are used in microservices.

Container in microservices is like an operating system in which all the codes, layout files, & libraries are run. It is comparatively light in weight. In other words, it consists of a collection of resources and applications to accomplish a specific task.

22. To what extent does Docker play a role in microservices?

The arrival of the docker technology when any developer develops any software in their computer environment, it worked fine but when it comes to production, its shows error because of the difference in a computing environment. This is similar in Microservices also. Docker solves this problem, In this case, In a container, there are multiple docker containers that are responsible for running each microservices. The memory or disk space for a docker container does not need to be allocated beforehand.

Microservices Interviews Questions For Experienced Candidate

1. What are Reactive Extensions in Microservices?

Reactive Extension is the approach of designing that calls multiple services and then develops a single response by integrating the results. The calls can be synchronous or asynchronous. A popular tool in distributed systems. The reactive extension is also called an Rx.

2. Explain the importance of reports and dashboards in microservices.

Monitoring a system is used reports and dashboards for microservices can help you:

• Sort out which microservice support which resources
• Determine which services are affected whenever changes are made to components.
• Determine maturity and compliance level from components

3. Explain the way to implement service discovery in a microservices architecture.

Netflix's eureka is the most efficient to set up service discovery. Microservice design architecture is a very simple process that does not add more weight to the application. Spring Cloud helps to simplify its use as much as possible and provide multiple annotations to hide complex concepts

4. Explain the term Spring Boot-Eureka in Microservices.

Eureka is a term used to describe an application that holds information about the client. It is part of the Spring Cloud bundle. In order to do this, it is necessary to develop the Eureka server and to run it on port 8761 by default.

5. What do you mean by end-to-end microservices testing?

End-to-end microservice testing is used to ensure the flow of an application through a business transaction. This testing is an uncoordinated and high-cost technique that is done through the user interface.

6. Explain continuous monitoring.

Continuous monitoring is the technology that is used to identify risk issues and compliance in a company's operational overhead and financial environment. To support efficient and effective operations, it consists of processes, a working system, and people.

7. What do you mean by Semantic Monitoring?

Semantic Monitoring or Synthetic Monitoring is basically automated testing and application that helps in monitoring errors in business processes. This technology helps to capture errors in transactions, identify performance issues of microservices, and provide an in-depth look at transaction performance.

8. Mention some well-known companies that utilize microservices

Microservices architecture is mostly used by large cap organizations or websites like:

• Netflix
• Amazon
• Microsoft
• Twitter, etc.

9. What do you mean by client certificates?

The client certificate plays an important role in securely authenticating their requests to remote services. This is a type of digital certificate that allows client systems to authenticate requests.

10. List three common tools used to develop microservices

Top 3 tools mostly used for Microservices included:

• Hystrix
• Docker
• Wiremock

11. What do you mean by Cohesion and Coupling?

Both Cohesion and Coupling happen simultaneously where high cohesion describes the relationship between two or more elements of a particular module. On the other hand, Coupling describes the relationship between two or more modules.

12. What is the use of containers in Microservices?

There are multiple use cases of the container in microservices such as it provides adequate support to the service oriented architecture and also provides more straightforward deployment of repetitive tasks.

13. Can you explain Mike Cohn’s Test Pyramid?

In software development, there is a need to automate the testing. So Mike Cohn’s Test pyramid helps to maximize the testing in the development of any software.