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)
Part 1: Legacy Estate Options
Chapter 2: Strategies for Modernizing IBM and Unisys Mainframes
Part 2: Architecture Options
Part 3: Azure Deployment and Future Considerations

What is a midrange system?

For this book, we consider IBM POWER-based systems to be midrange systems. There are other legacy systems such as Solaris and HP-UX that some may also consider to be midrange systems. However, we will cover those in Chapter 4.

POWER systems

IBM POWER systems use a high-performance computer chip and are the latest generation of big-endian hardware that power the iSeries (also known as AS/400) and AIX (IBM’s Unix variant) operating systems. POWER systems share some characteristics with the IBM zSeries hardware, such as the ability to be partitioned in logical partitions (LPARs), run big-endian bit ordering, and use Extended Binary Coded Decimal Interchange Code (EBCDIC) encoding. A single POWER platform can run LPARs with both iSeries and AIX. Finally, it’s important to understand that applications developed for POWER operating systems are not compatible with x86-based hardware. This means that some type of transformation will be necessary...