Book Image

Microsoft SQL Server 2008 High Availability

By : Hemantgiri S. Goswami
Book Image

Microsoft SQL Server 2008 High Availability

By: Hemantgiri S. Goswami

Overview of this book

<p>Every business has it's mission critical applications and data. Therefore, it is very important to keep database servers up and running all the time – 24 X 7. There is a need to store and process terabytes of data to cater for business needs, and it is vital to make data highly available.<br /><br />High availability is all about the site being accessible all the time. High availability solutions minimize the downtime for these mission critical applications.</p> <p>Microsoft SQL Server is a powerful relational database engine, widely used to store and maintain data in Enterprises of various levels be they small, medium or large.</p> <p>This book will teach you how best to use these readily-available options and save you time in making your websites highly available.<br /><br />This Microsoft SQL Server 2008 High Availability book will take you through pre and post installation concepts and common issues you come across while working with SQL Server HA. It will teach you how these various HA solutions can be installed using GUI and the command line. It will also show you how to troubleshoot common issues you may encounter whilst installing or managing the HA option in your environment. It provides references to external links for more advanced learning on the topic.<br /><br />This book starts with an introductory chapter into the windows domain, domain users and various handshake methods available with Windows server. It also offers information the different authentication methods available with SQL Server - giving you an insight into the importance of security. After you are through with the security aspects, your journey to installing SQL Server HA will start. It will cover the concepts of database mirroring, log shipping, clustering, and replication.<br /><br />By the end of this book you will be confident enough to take up the challenge to install any of the SQL Server HA options.</p>
Table of Contents (18 chapters)
Microsoft SQL Server 2008 High Availability
About the Author
About the Reviewers

Public and Private Network

In a clustering, each cluster node or every node that is a candidate for being a cluster node should have two Network Interface Cards (NICs) as a base requirement — one card can be used to configure the Public Network and second can be used to configure the Private Network.

  • Public Network: In a clustering environment, a network that is exposed to the public, that is, client systems to connect to is called the Public Network.

  • Private Network: A network that is used to connect two or more cluster nodes is known as the Private Network, also known as the Heartbeat.

    SQL Server uses this Heartbeat network for health detection between two or more nodes, especially in a single-node failover cluster. Consider a situation where we have configured a single-node failover cluster — Node1 and Node2. Node1 is holding ownership of the cluster resources and Node2 is in passive mode and has no access to or ownership of any cluster resources.

    In case of failure or unmanaged shutdown, or for any reason if Node1 is rebooted or shut down, the Private Network or Heartbeat between these two nodes fails and the Node2 of the cluster will become the active node. It will now have ownership of and access to all the cluster resources until it fails over to Node1.

    SQL Server MVP Brad McGehee, in his article, has mentioned some excellent points that should be considered while configuring the Public and Private Networks. The article can be found at