Microservices Interview Questions and Answers pdf by ScholarHat

Microservices Interview Questions and Answers pdf by ScholarHat

1. Microservices
Interview Questions
and Answers
Get insights into the technical and architectural considerations of
building microservices. Explore common microservices interview
questions and answers learn how to effectively discuss this modern
approach to software development.
by Scholarhat .SA

2. Advantages of Microservices
Architecture
Scalability and Flexibility: Microservices allow for independent scaling of individual services,
making it easier to handle fluctuations in demand and accommodate growth.
1.
Improved Agility: Smaller, autonomous teams can develop, deploy, and update services
independently, enabling faster innovation and reduced time-to-market.
2.
Technology Diversity: Microservices permit the use of different technologies and programming
languages for each service, allowing teams to choose the best-fit tools for their needs.
3.
Resilience and Fault Isolation: If one service fails, it doesn't bring down the entire system,
enhancing overall system reliability and availability.
4.

3. Challenges in Microservices
Implementation
Complexity in Service Discovery and Communication -
Coordinating and managing the interactions between autonomous
microservices can be challenging, especially as the number of
services scales.
1.
Ensuring Data Consistency and Transactional Integrity - Maintaining
data consistency across distributed services requires careful design
and implementation of compensating transactions and eventual
consistency mechanisms.
2.
Implementing Monitoring and Observability - Gaining visibility into
the health, performance, and behavior of a distributed microservices
architecture can be more complex than a monolithic application.
3.

4. Microservices Communication
Patterns
1 Direct Invocation
Services directly call other services through HTTP/RPC protocols. This
simple pattern works well for basic communication but can lead to tight
coupling.
2 Event-Driven Architecture
Services publish events to message buses, and other services subscribe to
relevant events. This decouples services and promotes asynchronous,
scalable communication.
3 API Gateway
A central API Gateway handles routing, protocol translation, and other
cross-cutting concerns, simplifying access for clients to the microservices
backend.

5. Service Discovery and Load Balancing
Service
Discovery
Service discovery is
the process of
dynamically finding
the network
locations of
microservices. This
allows services to
communicate
without needing to
know the exact IP
addresses or
hostnames
beforehand.
Dynamic
Registration
Microservices
register themselves
with a service
registry when they
start up, providing
details like their
network location,
version, and health
status. This registry
acts as a central
catalog of available
services.
Load Balancing
Load balancers
distribute incoming
client requests
across multiple
microservice
instances,
optimizing resource
utilization and
ensuring high
availability. They can
use various
algorithms to
determine the best
instance to route to.
Resilience
Service discovery
and load balancing
provide resilience by
automatically
routing around failed
or overloaded
microservice
instances. This helps
maintain application
availability and
performance even
when individual
components fail.

6. Containerization and
Orchestration
Microservices thrive on containerization, which packages each service
with its dependencies into portable, lightweight units. Orchestration
tools like Kubernetes then manage the deployment, scaling, and
networking of these containerized services across distributed
infrastructure.
Containerization and orchestration enable the agility, scalability, and
resilience that make microservices architectures so powerful.
Developers can rapidly build, test, and deploy services without worrying
about underlying system dependencies.

7. Microservices Testing and Monitoring
Rigorous Unit
Testing
Developers must
thoroughly unit test
each microservice to
ensure individual
components function
correctly before
integration.
Comprehensive
Monitoring
Effective monitoring
tracks key
performance
indicators, logs, and
alerts to proactively
identify issues across
the microservices
landscape.
Automated
Integration
Testing
Automated
integration tests
validate how
microservices
interact, reducing
manual effort and
ensuring end-to-end
functionality.
Chaos
Engineering
Intentionally
introducing failures to
test microservices
resilience helps
ensure the system can
withstand real-world
disruptions.

8. Microservices Security Considerations
Authentication & Authorization
Implement robust identity management and
access control to ensure only authorized
users and services can access sensitive data
and functionality.
Secure Communication
Utilize encryption, SSL/TLS, and secure
messaging protocols to protect data in
transit between microservices and external
systems.
Microservices Isolation
Leverage containerization and network
segmentation to isolate microservices and
limit the potential impact of a security
breach.
Vulnerability Management
Proactively scan for and address security
vulnerabilities in microservices code,
dependencies, and infrastructure to reduce
the attack surface.

9. Microservices Deployment
Strategies
1
Blue-Green Deployment
Migrate traffic between identical environments running different versions of
the application, enabling safe rollbacks.
2
Canary Deployment
Gradually roll out a new version to a small subset of users, monitor for issues
before full release.
3
A/B Testing
Split traffic between two or more versions, compare user metrics to
determine the optimal deployment.

10. Microservices Scalability and
Resilience
1
Horizontal Scaling
Adding more instances of a service to handle increased load
2
Circuit Breakers
Preventing cascading failures by isolating service
dependencies
3
Load Balancing
Distributing traffic across multiple service
instances
Microservices architectures must be designed for high scalability and resilience to handle
increasing traffic and ensure reliable performance. This involves techniques like horizontal scaling,
circuit breakers, and load balancing to dynamically adjust resources and isolate failures. By building
in these resilience patterns, microservices can continue serving users even during periods of high
demand or service disruptions.