Аннотация

In this book we provide you with an overview of Novell's high-availability solutions. We cover Novell Cluster Services (NCS) for Open Enterprise Server for both NetWare and Linux. We focus on the latest release of this software, but most information from this book is applicable to older versions of NCS as well. Our goal with this book is to give you a full overview of the process of designing and implementing a cluster. We provide insight into additional technologies such as iSCSI, Linux Heartbeat clustering, and Business Continuity Clustering. We also describe how to install popular applications into your cluster environment. In this book we have tried to go beyond the information provided in the online documentation. We not only describe how to configure NCS clusters, but also pay a good deal of attention to the "why" part of the configuration of a cluster because we would like you to understand what you are doing as well. This book is written for two different audiences. Administrators new to administering NCS, or clustering at all, will find enough information to get themselves going with Novell Cluster Services. And administrators who do already have experience configuring Novell Cluster Services will find that lots of details are included, especially on how to configure NCS on Linux servers.

In Chapter 1, "Introduction to Clustering and High Availability," clustering is introduced. This chapter is aimed in particular at novice cluster administrators, although even experienced administrators may find it helpful. Read this chapter if you want to know more about when you would use a cluster solution and how such a solution should be set up. Chapter 2, "Examining Novell Cluster Services Architecture," goes into the working of Novell Cluster Services; in this chapter we describe how the different components of an NCS network interact to make a working cluster. Also some clustering fundamentals such as Heartbeat packages and the Split Brain Detector (SBD) partitions are covered. This chapter is aimed mainly at those who want to know what's happening behind the scenes. If you are in a hurry and want to start as soon as possible, you can safely skip these two chapters.

Chapter 3, "Clustering Design," is an important one that everyone should read; it is about the design of a cluster. We've put all our field experience and some of the most important field experience of Novell technicians together in this chapter. We consider this one of the most important chapters in the book, and we do recommend that everyone read it, particularly because a proper understanding of how to design a cluster can prevent you from making many errors later.

Chapter 4, "Installation and Configuration," discusses installation of NCS. Read this chapter if you want to see more details on how to install NCS on NetWare, on Linux, or even in a VMware virtual environment. From this chapter, you also will learn how to add and remove nodes from the cluster. Chapter 5, "Creating Clustered Resources," gives an introduction to the configuration of clustered resources. Like Chapter 4, this chapter is particularly useful for people who have never worked with NCS before. Then in Chapter 6, "Cluster Management," you will find an overview of all the ways to administer an NCS environment. It explains how to use Remote Manager and iManager, but also how to use SMTP alerting in an NCS environment. Even experienced administrators of NCS clustering may find some information they weren't aware of yet.

Starting with Chapter 7, "iSCSI," some more advanced topics are covered. Most clusters do need a solution that offers shared storage, and in general iSCSI is considered a good and affordable solution to do just that. From the information in this chapter, you will learn how to configure NetWare as an iSCSI target and connect the iSCSI initiator software on Linux to that iSCSI target. We have chosen not to include any other information on shared storage solutions, the main reason being that almost all SAN solutions are rather proprietary. Chapter 8, "Cluster-Enabled Applications," can be considered the core of this book. In this chapter, which is one of the longest in the book, you can find information on how to configure our selection of applications in an NCS cluster. We discuss configuration of some of our favorites, such as iFolder and GroupWise, but some classics from the Linux environment are also covered in this chapter. Next, Chapter 9, "Advanced Clustering Topics, Maintenance, and Troubleshooting," discusses advanced technologies that can be applied to NCS environments. In this chapter, for example, you can read how to re-create the SBD partition when it fails and how to make a proper backup of your cluster. This chapter typically is meant for an administrator who already knows about the nuts and bolts of Novell Cluster Services and wants to upgrade his tuning and troubleshooting skills.

The last three chapters are optional in many cases. Chapter 10, "Upgrading Clusters," discusses how to upgrade an existing cluster to NCS. Chapter 11, "Using SUSE Linux Enterprise Server Clustering Options," tells you how to use the Heartbeat cluster solution in a SUSE Linux Enterprise Server environment. We can recommend this chapter because in the near future the NCS core will be upgraded to the open-source software from the Heartbeat project.

Finally, in Chapter 12, "Introduction to Business Continuity Clustering," you can read how to create a cluster of clusters using Novell's Business Continuity Services.

We put a lot of effort into writing this book and really hope you enjoy reading it! If you ever have any questions or remarks, you can reach us at the following email addresses: