Book Image

Modernizing Legacy Applications to Microsoft Azure

By : Steve Read, Larry Mead
Book Image

Modernizing Legacy Applications to Microsoft Azure

By: Steve Read, Larry Mead

Overview of this book

Organizations have varying circumstances, objectives, and prerequisites when contemplating a hyper-scale cloud solution transformation to a platform such as Azure. Modernizing Legacy Applications to Microsoft Azure uncovers potential scenarios and provides choices, methodologies, techniques, and prospective possibilities for transitioning from legacy applications to the Microsoft Azure environment. You’ll start by understanding the legacy systems and the main concerns regarding migration. Then, you’ll investigate why distributed architectures are compelling and the various components of the Azure platform needed during migration. After that, you’ll explore the approaches to modernizing legacy applications and the Rs of modernizing (i.e., rehost, refactor, rearchitect, and retire). You’ll also learn about integration approaches and potential pitfalls. By the end of this book, you’ll be well equipped to modernize your legacy workloads while being aware of pitfalls and best practices.
Table of Contents (18 chapters)
1
Part 1: Legacy Estate Options
3
Chapter 2: Strategies for Modernizing IBM and Unisys Mainframes
6
Part 2: Architecture Options
10
Part 3: Azure Deployment and Future Considerations

What if you want to transform a monolith to cloud native?

Now, we will look at creating a cloud-native approach for transformation from a monolith.

The tyranny of locality

Before we dive into the mechanics of what we need to consider when we are migrating from a monolithic architecture, let’s consider the fundamentals. In a monolith, by definition, almost every resource we need to access is local, or very close to local. This means that the way you approach your development is different. In a distributed environment, this is not the case, hence the distributed part of the term. Typically, we need to negotiate a network and security handshake, which is time-consuming, and this is one of the essential differences between the two paradigms. Let’s be very clear here: no one model is better than the other, but they are fundamentally different. In a monolithic architecture, we can get away with things such as polling (that is, querying a resource multiple times to detect...