Articles - Legacy application modernization

Enterprises are continuously modernizing their application portfolios to meet digital business imperatives. Modernizing applications by adopting microservices requires a new set of tools for efficiency and speed. This brings up the challenge of navigating through tools and frameworks. My blog aims to guide you by reviewing a few core tools that help with microservices driven legacy application modernization.

Industry standard container tools

There are several names that anyone researching microservices will come across.

One of those names is Docker.

Docker is a tool that makes it easier to deploy and run applications by using containers. And it is the industry standard for containerized applications. In containerization, a developer packages an application along with all its dependencies, libraries and its entire environment in a unit called a container. A Docker container is a lightweight, isolated, executable package of software. It includes everything needed to maintain, ship and deploy an application and also run it portably.

In Stack Overflow’s developer survey, users praised Docker as one of the most loved platforms. Many developers said they wanted to start using Docker.

Cluster and container management

Software modernization via microservices largely involves using containers.

Depending on the size of your organization, you may need multiple containers for a single application. In many cases organizations run multiple applications that are deployed on hundreds of containers within a microservices architecture. For example, organizations may face issues with ensuring application availability at all times. Think of how your favorite search engine is reliably available on multiple devices.

Or maybe the challenge is load balancing to ensure the load is distributed properly. And that no single server is overburdened. There may be issues with scaling up or down depending on user load. This may lead to using multiple containers or a cluster of containers for an application. There are several other challenges involved with a microservice architecture run in a containerized structure. You still have to manage processes like deploying, scheduling, scaling, batch execution, rollbacks, and monitoring. The volume of containers to be managed and the challenges that follow dictates the need for tools to deal with container orchestration.

Kubernetes

The industry-standard for container and cluster management is a tool called Kubernetes. Kubernetes deals with orchestrating containers and clusters. Google built Kubernetes over fifteen years ago. In 2014 Kubernetes was made an open-source tool. The effective appeal of Kubernetes is in how long it has been used to run Google’s massive systems. Last year, containerjournal.com noted a 51% increase in Kubernetes adoption. Kubernetes cluster services help an organization manage the desired state of their applications. For example, an organization provides Kubernetes cluster services with the configuration suited to the optimal functioning of its application landscape. This means that the cluster services are given a specific configuration via an API. This will include configurations for the smallest unit of deployment called a pod. A pod may have one or more containers.

Each container will have a specific static container image given in the configuration file. Each pod may have multiple container images and several replicas. This quickly becomes a mammoth task for an organization with a sizeable microservice architecture. It is up to the cluster services to automate and run the configuration on the organization’s container infrastructure. And to perform all of the management processes that go along with this from deployment to monitoring.

OpenShift - An alternative to Kubernetes

OpenShift is a popular alternative container application platform. It has a private container registry. This can be used as a standalone unit or installed as a Kubernetes application. The OpenShift container platform is a Platform-as-a-service that has several pros and cons.

OpenShift comes with limitations to the Linux distributions it can be installed on. On the other hand, Kubernetes can be installed almost anywhere. OpenShift is easier to use for beginners. And OpenShift has better management of container images than Kubernetes. OpenShift also has more strict security policies than default Kubernetes. This is why it is an attractive alternative for IT organizations that place a premium on security.

Microgateway or service mesh?

Microservice architecture presents complex new problems. As your organization’s distributed network of microservices grows, it also increases in complexity. These complexities can be operational requirements. For example, access control, authorization, and authentication.

Microgateways present one way to tackle the complexities of microservice architecture by facilitating internal communications between distributed microservices. Microgateways are effectively an inner gateway paired with a microservice instance. Microgateways on each service are ready to spin up and provide communication connections. Alternatively, a layer of infrastructure called a service mesh may be used to enable more flexible communications.

The term service mesh describes the network of microservices that make up a microservice architecture and all the connections between them. Service meshes perform all the same critical actions achieved by microgateways. However, it has an added layer of abstraction that allows for better communication connections.

Istio

Istio is a platform-independent service mesh tool. Istio reduces the complexities of legacy modernization in a distributed application landscape. Istio’s service mesh satisfies many of the requirements of running microservice applications. It has the highest numbers of stable protocols for its traffic management and observability features.

It gives you increased visibility, behavioral insights and operational control over all the distributed microservice applications in its service mesh. The monitoring capabilities of Istio can be augmented with adapters like Prometheus. These tools enable better metrics collection and data visualization.

Go for quality and experience

There is no one-size-fits-all in Microservices tools. Perhaps your microservices would benefit more from a service mesh than a Micro gateway structure. Or maybe you would gain more from OpenShift than Kubernetes.

An experienced guide can help steer you in the right direction.

Last year, Torry Harris Integration Solutions won two important UK Digital Experience Awards. One of those awards was in the “best digital change and transformation” category. An experienced and specialized service provider like Torry Harris can guide your transformation using microservices. Learn more about Torry Harris’ Microservices solutions here.