Book Image

Implementing NetScaler VPX??? - Second Edition

By : Marius Sandbu
Book Image

Implementing NetScaler VPX??? - Second Edition

By: Marius Sandbu

Overview of this book

With a large demand for responsive websites and availability of services, IT administrators are faced with an ever-rising need for services that are optimized for speed. NetScaler VPX is a software-based virtual appliance that provides users with the comprehensive NetScaler feature set. Implementing apps and cloud-based services is much easier with its increased service performance and integrated security features. This book will give you an insight into all the new features that NetScaler VPX™ has to offer. Starting off with the basics, you will learn how to set NetScaler up and configure it in a virtual environment including the new features available in version 11, such as unified gateway and portal theme customization. Next, the book will cover how to deploy NetScalar on Azure and Amazon, and you will also discover how to integrate it with an existing Citrix infrastructure. Next, you will venture into other topics such as load balancing Microsoft and Citrix solutions, configuring different forms of high availability Global Server Load Balancing (GSLB), and network optimization. You will also learn how to troubleshoot and analyze data using NetScaler's extensive array of features. Finally, you will discover how to protect web services using an application firewall and will get to grips with other features such as HTTP, DOS, and AAA.
Table of Contents (10 chapters)
9
Index

Global Server Load Balancing


Now we also have Global Server Load Balancing (GSLB). This is not a high availability feature per say; however, as the name describes, it is a load balancing feature.

GSLB works with the help of DNS. It allows us to deliver a service from different data centers spread across different geographical locations; this helps us in case of data center failures and disaster recovery.

It can also help to spread the load across different locations with its proximity feature, and allows users to be sent to the closest data center. This type of feature is already in use today is many large web services such as Google, Facebook and so on.

So, let's take a closer look at how GSLB works. First off, it is important to know how DNS functions, as this is the fundamental component in GSLB.

When a user connects to a service, for example, www.myservice.company.com, the client will send a DNS request to its DNS server, which is the NS server. The DNS server of the client will send a recursive...