Book Image

Troubleshooting NetScaler

By : Raghu Varma Tirumalaraju
Book Image

Troubleshooting NetScaler

By: Raghu Varma Tirumalaraju

Overview of this book

NetScaler is a high performance Application Delivery Controller (ADC). Making the most of it requires knowledge that straddles the application and networking worlds. As an ADC owner you will also likely be the first person to be solicited when your business applications fail. You will need to be quick in identifying if the problem is with the application, the server, the network, or NetScaler itself. This book provides you with the vital troubleshooting knowledge needed to act fast when issues happen. It gives you a thorough understanding of the NetScaler layout, how it integrates with the network, and what issues to expect when working with the traffic management, authentication, NetScaler Gateway and application firewall features. We will also look at what information to seek out in the logs, how to use tracing, and explore utilities that exist on NetScaler to help you find the root cause of your issues.
Table of Contents (17 chapters)
Troubleshooting NetScaler
Credits
Notice
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Integrated Caching


A good majority of content on the web is fairly static. Granted, the current nature of the web means that new content is created all the time, but it doesn't change with every request and some items, like the branding on a company's homepage, stay unchanged for years. Integrated Caching is an HTTP feature on the NetScaler that allows potentially massive savings on bandwidth and server CPU utilization by storing a copy of previously requested objects in its RAM and serving them to users over and over again as long as it is considered valid.

Let's look at some caching-related terms that we will use in this chapter:

  • Origin server: This is the server in the backend that generates and owns the original content

  • Cache hit: This means that a request that has landed on the NetScaler can be responded to with an object from the cache

  • Cache miss: The request has to be sent to the origin server

  • Revalidation: This is the NetScaler going back to the server to verify that the content is...