From Monolith To Microservices – The Why And How

From Monolith To Microservices - The Why And How
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As far back as 2008, Netflix in its earlier avatar encountered a network outage at one of its data centers, leading to a temporary shutdown of its DVD rental services for three days. Now imagine the impact considering this was their only revenue stream. No rentals for 3 days meant no revenue for 3 days. They realized they needed a more dependable infrastructure that won’t break down due to a single point of failure. Netflix replaced its monolithic architecture with microservices. Yes, that’s how far back we can go to sight signs of microservices-led success. 

Since then, several enterprises like Spotify and eBay have moved from monolithic to microservices architecture, improving their business outcomes. Today, over 73% of enterprises have already adopted microservices.

Why The Shift From Monolith To Microservices?

Before understanding why enterprises are shifting to microservices, let’s know the differences from traditional architectures.

In a monolithic approach, the application is developed and deployed as a single unit on the same server. Everything is created simultaneously. While it simplifies the development, testing, and product release process, scaling or updating the application or fixing a bug can become complicated. Sometimes it could take almost a week to change a few lines of code, create a new build, and deploy the entire system. In an agile world, delays and downtimes during frequent changes can hurt the enterprise’s business. That’s why most enterprises are shifting to microservices.

Microservices involve developing and deploying applications as a set of small services., i.e., every service has its separate framework, programming language, and database. They work independently and have no impact on other components. Microservices are the perfect solution for building large, complex, and dynamic applications requiring frequent upgrades. Since microservices are built on small, independent components, the applications are easy to scale, flexible, and maintain. It allows the developers to focus on innovation without worrying about downtime and launch the application quickly to meet customer expectations.

Let’s find out what enterprises can do to shift their infrastructure from monolith to microservices.

8 Tips For Migration From Monolith To Microservices

Choose the right microservices architecture approach

There are three approaches to building the microservices architecture:

  • Events-driven microservices architecture: It helps the microservices to communicate with each other when a real-time event occurs and acts on it. It is helpful for applications that manage large real-time data volumes and events.

  • Domain-driven microservices architecture: In this approach, every microservice is organized around specific business domains and sub-domains and is responsible for specific business capabilities. It is helpful for large enterprise applications with complex systems, multiple business domains, and business capabilities.

  • API-driven microservices architecture: In this approach, the microservices are designed for the specific parts of the APIs. It improves the flexibility and reusability of microservices and makes integration with other systems and applications hassle-free.

Choose the approach that meets your business needs and solves the application constraints.

Do a readiness assessment

Before starting the migration, do a readiness assessment of the current state of the infrastructure and applications, analyze the internal policies and team competence, and check if the enterprise is ready for the change. These are critical steps because they will help you identify the business priorities that will benefit from the migration and the potential roadblocks you could face in the process. Aligning the priorities with business goals will help the enterprise benefit from the migration and plan a smooth transition.

Identify the component dependencies

Start by creating an inventory of a system’s different functions and capabilities and map out the associated code objects. This is essential because it will help identify component dependencies, duplications, and redundancy. You can manage and maintain the system better by retiring or consolidating the identified redundant services and applications that duplicate each other’s functionalities and data. It will reduce the complexity during migration and set the stage for a successful migration. By identifying and mapping component dependencies and taking appropriate action on them, you can develop, maintain, and optimize each service efficiently.

Choose the services and infrastructure to migrate

Start by prioritizing the services to move. You could begin by selecting the ones that don’t work well in monolithic architecture or those with fewer dependencies. Next, choose the infrastructure to host. Ensure the cloud platform is scalable, flexible, cost-effective, and offers authorization tools and secure communication protocols. 

Choose the right tools

You need the right tools to make the migration process smooth and manageable, reduce complexity, and minimize risks. To choose the right tool, evaluate the challenges you face in migration. It will help you find the ones best suited to your needs. Besides that, ensure that it supports scalability, offers security features like encryption, authentication, and access controls, and minimizes challenges faced during the migration process.

Set up communication between services

Microservices must communicate and work together to provide the same functionality as a monolithic application. Communication will help each service to handle the load, errors, and scaling requirements efficiently. The communication between the different services can be synchronous (the caller waits for a response) or asynchronous (where the service sends multiple messages simultaneously). Typically, enterprises choose asynchronous communication while moving the application to microservices. To set up communication between services, set up a public API for client application calls and a backend API for interservice communication.

Migrate the data

Migration of data from monolithic to microservices can be complex and time-consuming as it involves transferring the legacy database, business logic, and the behavior supporting the application to the new architecture. If your enterprise takes the phased migration approach, you might also need access to old data from the old monolithic application. You can set up an API to retrieve from the application and other services smoothly.

Deploy and monitor the progress

Once the migration is complete, deploy the new architecture and monitor it closely for issues and progress. Test the new services to ensure they function as expected without any breakdown. Once all the microservices perform flawlessly, remove the glue code that facilitates communication between the legacy monolithic system and the new microservices system and filter and prevents unnecessary data from entering the new architecture. You can retire the old application after removing the glue code.

How To Begin?

Migrating from monolith to microservices benefits business, but you will also face challenges in setting up the architecture, configuration management, debugging, and scaling up the architecture.

Partnering with a specialist is essential, given the time and resources required in the migration process. A specialist will understand the business need and organization setup and guide you through the end-to-end migration process. They will help you adopt microservices and set the tone for continuous innovation and business continuity.

If you need more information on migration or product development, contact us. We will be happy to help.