3.6.0 MxDB for SQL Server Installation and Administration Guide (5697-7088, December 2007)

Chapter 2: Introduction 5

Then determine how you want to configure the Virtual SQL Servers. Each

Virtual SQL Server needs a primary node and one or more backup nodes.

The backup nodes for each Virtual SQL Server must contain the same set

of SQL instances as the primary node. Following are some sample

configurations.

NOTE: A primary SQL instance and its backup SQL instances must have

the same name. For example, if you install an SQL instance called

“instance1” on the primary node, you will also need to install an

instance called “instance1” on the backup node.

Active-Active

In this configuration, the nodes in the matrix back up each others’ Virtual

SQL Servers. In the following example, the Virtual SQL Server “virtual1”

is primary on node1 and has a backup on node2. The SQL instance

“instance1” is associated with this virtual server and exists on both nodes.

Clients can access the virtual server using virtual1\instance1.

Similarly, Virtual SQL Server “virtual2” is primary on node 2 and has a

backup on node1. Two instances (instance2 and instance3) are associated

with this virtual server and exist on both nodes.

Many-to-One

In this configuration, one node provides backups for the Virtual SQL

Servers running on the other nodes. In the following example, nodes 1, 2,

and 3 are each hosting a Virtual SQL Server. These virtual servers all use

node 4 as a backup. The instances associated with the Virtual SQL Servers

are all installed on backup node 4.

Node 2

Primary : virtual2

instance2

instance3

Backup: virtual1

instance1

Node 1

Primary: virtual1

instance1

Backup: virtual2

instance2

instance3