Annett R. Working with Legacy Systems: A practical guide to looking after and maintaining the systems we inherit

Packt Publishing, 2019. — 152 p. — ISBN: 978-1838982560, 1838982566.Understand the crux of legacy systems ― their architecture, analysis, and security constraintsKey FeaturesUnderstand what are legacy systems and learn various strategies to maintain them
Deep dive into the basic and advanced architectures of legacy systems
Discover how to analyze and secure the legacy systemsBook DescriptionThe latest edition to our range of products is Packt Select - the new range of books with a broad spectrum of information on unique topics. We have identified your requirements, searched for the best books available, and we now offer these to you. With these books, you'll enjoy a smooth learning experience with the usual Packt "must-haves" of real-world examples and best practices.
New technologies are continuously being introduced in the I.T. industry. While learning those is important, maintaining legacy systems is equally necessary to ensure that the I.T infrastructure of your organization functions to its best abilities. Sound knowledge of techniques that can be used for maintaining legacy systems, can help you avoid many pitfalls.
You'll begin the book with a quick understanding of what a legacy system looks like, how it works, and what are some common issues in it. Then, you'll explore the architecture of a legacy system in detail and learn each of its components. You'll learn and use various techniques to analyze a legacy system. After learning about the security constraints associated with legacy systems, you'll explore ways to overcome these constraints and secure the systems. Towards the end of the book, you'll learn how easily make changes in the legacy systems to enhance their performance.
By the end of this book, you'll have skills and confidence to work with legacy systems and efficiently maintain them.What you will learnPerform the static and dynamic analyses of legacy systems
Implement various best-practices to secure your legacy systems
Use techniques, such as data cleansing and process cleansing to stabilize your system
Apply structural changes in your legacy system to make it highly available
Identify and resolve common issues with legacy systems
Gain knowledge of various tests that can help secure and maintain your legacy systemsWho this book is forThis book is ideal for IT professionals, who want to understand the working and maintenance of the legacy systems. Prior knowledge of working with legacy systems is not needed to complete this book.
Robert Annett has been a developer since 1995 and has worked in industries from energy management to investment banking. Much of his work has involved upgrading and migrating legacy systems, with the occasional green-field project (involving integration to legacy systems, of course). He has worked in the IT industry long enough to realize that all successful systems become legacy eventually.Definition, Issues, and Strategy
Investigation and System Review
Making Changes