How to migrate from monolithic to cloud-native applications

Companies are modernizing their legacy applications to make them digital age ready. They are also investing their resources to move their legacy monolithic applications to modern cloud-native applications.

These companies use modern tools and techniques to build highly scalable, flexible, and resilient applications built on cloud infrastructure. In this blog, we will investigate the business case of monolithic to cloud-native applications migration. We will also discuss the best practices to make your migration exercise as advantageous as possible.

Is the cloud-native application a silver bullet?

The answer depends on your business goal. A monolithic application is your best bet if you have a small developer team, a low development budget, want to develop a quick functional version of your product and less complex infrastructure requirements.

However, monolithic applications have poor scalability due to a high level of coupling. The entire system needs to be redeployed with every update. As the application grows, adding new features is complex and maintenance is expensive. Since the entire codebase is coupled and highly dependent, bugs and crashes can affect the whole system.

Advantages of cloud-native applications

• Increase efficiency due to DevOps and continuous delivery (CD) agile practices, use of automated tools, cloud services, and modern design culture to build scalable applications rapidly.
   
• Save costs on operational expenditures as companies don't have to invest in the procurement and maintenance of costly physical infrastructure.
   
• Application availability during feature updates.
   
• Fast development due to the availability of ready-to-deploy containerized applications with DevOps practices. This allows developers to respond to changes quickly.
   
• Platform independence as the cloud provider takes care of hardware compatibility and developers can focus on delivering value instead of setting up the underlying infrastructure.
   
• Cost-effective operations as you only pay for the resources your application uses and do not have to provide extra resources that sit idle for most of the year.

Why migration?

The decision to move from a monolithic software architecture to cloud-native microservices is triggered by the need to accelerate application development and optimize infrastructure costs. Apart from that, cloud-native applications use a collaborative approach and are highly scalable on different platforms. It allows developers to automate building, testing, and deploying procedures.

Cloud-native applications have adequate isolation between each service. When one service fails or is prone to a security attack, the impact of the incident is isolated to just that service. Also, cloud-native applications bring deeper visibility into incidents in each of the services.
 

Migration best practice

• Build a migration business case - Get realistic about what you can achieve and then build a conservative business case articulating the migration benefits, associated costs, and risks.
   
• Beware of security exposure - Moving your application to the cloud increases your security exposure. Implement security policies and procedures before you begin migration. Be vigilant about users’ data policy considering the latest legal compliance framework.
   
• API-First development - Define the interfaces of applications to know the input/output formats of applications upfront, accelerate development by building mock-ups, and review security and data quality standards early on.
   
• Develop a robust monitoring system - The monitoring solution includes Application performance management to monitor CPU usage, memory availability, traffic, and error rates.
   
• Automate alerts when critical thresholds are breached or unexpected events occur.
   
• Use existing cloud infrastructure developed by cloud service providers.
   
• Consult with industry peers to discuss case studies for organizations similar to yours which have migrated to the cloud, and understand their challenges and learnings.  

Step-by-step migration process

Identify modules and components in monolithic applications.

Each of the modules in the monolithic application has three components – data objects (logical data construct) , data actions (commands used on data to perform the task), and job to perform/use cases ( function called to perform the task). Identification of these components helps the system architect determine actions to be performed on data sets.

Organize components that have similar functionalities.

The objective is to have one microservice performing a particular task.

Identify component dependencies.

Architects can perform this task using static analysis of the source code to search for calls between different libraries and datatypes.
 

Components group identification.

Classify components into Microservices and Macroservices groups.
 

Develop APIs for remote user interface.

Design and develop a unified API through which the user interfaces with the system and manipulates the data. Ensure it is scalable to accept new data sets, functionalities, objects, attributes, actions and existing data interactions are not altered significantly. Once the API layer is developed, all new functionality is added through the API and not through monolithic applications.

Migrate the components to Macroservice.

This is an interim step before components are moved to microservices. It makes the migration easy as it provides insight into how to further classify these components into Microservices.
 

Migrate Macroservice to Microservice.

Once the components are migrated to Macroservice, grouped and organized, the system architects must migrate these components of a monolithic application to Microservice from Macroservice.
 

Deployment and testing.

Once a microservice is ready for deployment, the next step is integration testing and deployment. Configure the monolithic system to use the new service for its data needs instead of its legacy data store.
 

Microservices are gaining traction and there is a high adoption rate. At the same time, there are instances where monolithic applications are more relevant. It all drills down to your business requirements and what you want to achieve. There will always be a tradeoff if you opt for one over the other.

To find out more about how Proventeq can help you build a business case - visit our webpage or contact our migration experts directly for a 1:1 session.