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 is the Strangler Fig pattern?

To understand what the Strangler Fig pattern is, it is probably best to describe where it derived its name from.

In nature, a fig tree often begins to grow on another tree (the host tree) and finally wraps its roots around it, slowly strangling and engulfing the host tree’s growth. This phenomenon is known as the Strangler Fig pattern. The host tree is eventually killed and replaced by a new fig tree as a result of the strangler fig’s roots absorbing nutrients and water from it. This pattern is an illustration of the natural process of resource rivalry, in which one species subjugates another by using its resources.

In software development, the Strangler Fig pattern is used as a metaphor to describe how a new software system replaces an older one by gradually absorbing its resources and functions without substantially altering the previous system.

With this pattern, it is implied that certain services will be migrated first...