Strangler fig pattern in Microservices - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Understanding the core idea of the Strangler Fig Pattern

Which of the following best describes the main goal of the Strangler Fig Pattern in system design?

A To replace a legacy system gradually by building new features as separate components that eventually take over all functionality.

B To immediately rewrite the entire legacy system from scratch to improve performance and scalability.

C To run the legacy system and new system in parallel indefinitely without integration.

D To create a monolithic application that handles all legacy and new features in one codebase.

💡 Hint

Think about how the pattern helps in transitioning from old to new without big risks.

The Strangler Fig Pattern focuses on gradually replacing parts of a legacy system by building new components that take over functionality step-by-step, reducing risk and downtime.

❓ Architecture

intermediate

Identifying components in a Strangler Fig architecture

In a Strangler Fig Pattern implementation, which component acts as the traffic director that routes requests between the legacy system and new microservices?

A Message Queue

B Load Balancer

C API Gateway

D Database

💡 Hint

Consider which component controls request routing and can decide where to send each request.

The API Gateway acts as the traffic director by routing requests either to the legacy system or to new microservices during the gradual migration.

❓ scaling

advanced

Scaling challenges during Strangler Fig migration

What is a common scaling challenge when running both legacy and new systems simultaneously in a Strangler Fig migration?

A Reducing the number of microservices to avoid complexity.

B Ensuring consistent data synchronization between legacy and new components.

C Eliminating all legacy system dependencies immediately.

D Deploying the new system on the same hardware as the legacy system.

💡 Hint

Think about data consistency when two systems handle parts of the workload.

During migration, both systems may need to share or synchronize data, which can be complex and affect scaling.

❓ tradeoff

advanced

Tradeoffs in choosing Strangler Fig Pattern

Which tradeoff is most associated with using the Strangler Fig Pattern for system migration?

A No need for testing since old system remains untouched.

B Faster migration but higher risk of breaking existing features.

C Complete system rewrite with no backward compatibility.

D Longer migration time but reduced risk of system downtime.

💡 Hint

Consider the balance between speed and safety in migration strategies.

The Strangler Fig Pattern trades longer migration time for safer, incremental replacement, minimizing downtime and risk.

❓ estimation

expert

Estimating capacity needs during Strangler Fig migration

You are migrating a legacy monolith to microservices using the Strangler Fig Pattern. The legacy system handles 10,000 requests per second. You plan to migrate 30% of functionality to new microservices initially. What is the minimum expected request load on the new microservices after migration starts?

A 3,000 requests per second

B 7,000 requests per second

C 10,000 requests per second

D 30,000 requests per second

💡 Hint

Calculate the portion of total requests handled by new microservices based on migrated functionality percentage.

If 30% of functionality is migrated, the new microservices will handle approximately 30% of the total 10,000 requests, which is 3,000 requests per second.