What challenges do organizations face when implementing Microservices?

Although the benefits delivered by the microservices architecture such as improved scalability and agility, support for multiple technologies, fault isolation, and so on remain true, enterprises may still encounter difficulties in building and deploying microservices.

It is not unusual to encounter similar setbacks as other organizations have in implementing microservices; however, understanding and dealing with those challenges help develop best practices for getting value and exploring the numerous opportunities a microservices architecture offers.

Here are some shortcomings that organizations face when implementing microservices, and some suggested solutions.

The control of the entire microservices life cycle, which includes how it is implemented, tested, versioned, deployed, and maintained can be complex and eventually become clumsy, especially when the number of microservices increases. For organizations at the early stage of their microservices implementation, this may not be a challenge. However, as more microservices are developed, there is a high chance of encountering problems such as:

Duplication and redundancy,
Discoverability and traceability,
Lack of stability
Usability and reusability,
Dependency and,
Troubleshooting.

Failing to employ good microservices management practices could lead to a loss of efficiency and hinder the organization's growth.

Therefore, it is important that organizations prioritize employing a proper microservices management platform that can support the development, deployment, and maintenance of their microservices and dependencies.

Although every organization has to determine the most suitable approach for developing or acquiring the right platform for them, it is important that they put into consideration the degree of independence, operational complexity, continuous delivery and scalability, team organization, code organization, and their overall organizational goals, before making that decision.

Monitoring help organizations to:

Understand the overall health of the application
Obtain insight into the performance of each service that makes up an application
Ensure the API transactions are always available
Isolate complicated endpoints
Optimize end-user experience

Considering the speed and dynamic nature of microservices, organizations will have to monitor:

CPU Usage: The development, deployment, testing, and shredding of a single service can happen in a split second. Therefore, causing a high CPU usage and eventually lead to more expenses. Monitoring CPU usage with this rate of change i.e. every second can be challenging.
Scalability: Monitoring thousands of services running in different continents, regions, and zones. With each service having separate versions, containers, and instances, monitoring scalability can present a big problem.
Communication flow: Virtualizing the flow of a large number of interconnected independent services and dependencies can pose unique sets of challenges. For instance, conceptualizing how a "search" service would successfully communicate with catalog, price, location, and other services without latency.
Service Failure: Consider a significant number of microservices that perform their function(s) in milliseconds. Monitoring it to determine when a service failure occurs, how many service(s) were affected by the failure, and the decision to either stop the service or carry on the service with reduced functionality in the same milliseconds is a challenge.
Testing: As the number of microservices grows, monitoring testing, particularly an End-to-End test, becomes more expensive especially on a cloud stack.

However, the appropriate monitoring of microservices can provide an early warning system for application decline or failure, an overall analysis of the performance of each service, along with a signal as to where and when enabling development and operations teams to identify and resolve the issues quickly.

When employing the use of a monitoring tool, it is important to ensure it has the capabilities for:

Logging
Metrics
Tracing
Message correlation.

In addition, Monitoring requirements should be considered from the very beginning of the microservices lifecycle and requires contributions from both the development and operations teams. It is a critical part of the operational support of microservices architecture and it requires more real-time attention and proactive monitoring.

Testing and quality assurance is much more complex in a microservices architecture owing to the different services making up an application, each microservices must be tested separately, and the overall application must also be tested to ensure it is performing properly.

Testing microservices may present difficulties like

Availability: the possibility to get multiple independent services ready for test at the same time is extremely low.
Fragmented testing: Microservices are built to work independently, and together with other loosely coupled services. That means development teams need to test every service in isolation, along with testing the entire microservices.
Knowledge gaps: The quality assurance team will need to have a strong knowledge of each service to write test cases effectively.

With these testing challenges, it is best to take a pragmatic risk-based approach to test the critical parts of the application.

There are a few core microservices testing methods that development teams will have to critically consider. Not only will they help make sure that the service is performing accurately, but they will also guarantee the level of monitoring needed to always make the right decisions on the move.

These testing methods include:

Performance testing.
Integration testing.
Unit testing.
Component testing.
Contract testing.
End-to-end testing.

In addition, unit testing of the individual modules, Integration testing, contract testing of the service APIs, and End-to-End Testing can be adopted as some of the pre-production testing techniques to test the application but with defined goals and scope.

Implementing the microservices architecture style requires some orientation and time. The migration to microservices requires cultural and organizational changes.

Moreover, moving forward with the implementation of microservices using existing process may lead to

Delayed testing
Rigid development and deployment, and
Blind feedback.

Before an organization can start the migration or development process, having a DevOps automation and Agile culture in place is a great foundation.

Each microservice team operates as an independent faculty. Also, encouraging the structure that allows development teams to work in small groups, work independently, and offer more control and increased productivity.

However, each development team must be able to manage the entire lifecycle of their service, including maintaining and managing an independent test container.

Consequently, organizations will need to determine if employees have the knowledge required to successfully implement or migrate to a microservices-based application.

On top of that, include people with DevOps and release automation skills in each development team. Consider this an asset that will become increasingly important as the organization scales.

Migration to microservices often involves transferring the competencies and decision-making power from managers to individual development teams. Although, that change to the organization chart can be difficult for some members to accept.

However, the first step toward successful cultural change requires educating top leaders in the organization on how to carry out the initiative, rather than prevent their development teams from being productive.

And finally, organizations will need to mitigate the communications challenges associated with this cultural change because the independent microservices often mean that development teams would not always have overall visibility.

The microservice architectural style is one of the prominent and relevant design approaches for developing a standard application.

However, the additional complexity in the operations and troubleshooting of this architectural style creates its own set of challenges. Therefore, being proactive and educated about those challenges and how to address them is a sure way to gain most of the microservices benefits.