Recipe 10.1 Listing SQL Servers

Problem

You need to obtain a list of SQL Servers available on the network.

Solution

Use SQL Server Distributed Management Objects (SQL-DMO) to retrieve a list of available SQL Servers.

You'll need a reference to the Microsoft SQLDMO Object Library from the COM tab in Visual Studio .NET's Add Reference Dialog.

The sample code retrieves and displays a list of all SQL Servers running on a local network segment by using SQL-DMO through COM interop.

The C# code is shown in Example 10-1.

Example 10-1. File: ServerListForm.cs

// Namespaces, variables, and constants
using System;

//  . . . 

serverListListBox.Items.Clear( );

// Create a SQL Distributed Management Objects (SQL-DMO)
// application object.
SQLDMO.Application dmo = new SQLDMO.Application( );
// Retrieve the available servers.
SQLDMO.NameList serverNameList = dmo.ListAvailableSQLServers( );

// Iterate over the collection of available servers.
for(int i = 0; i < serverNameList.Count; i++)
{
    if (serverNameList.Item(i) !=  null)
        serverListListBox.Items.Add(serverNameList.Item(i));
}
serverListListBox.Items.Add("End of list.");

Discussion

SQL Server Distributed Management Objects (SQL-DMO) is a collection of objects that encapsulate SQL Server database and replication management. SQL-DMO is used to automate SQL Server tasks, create and administer SQL Server objects, and install and configure replication. You can use SQL-DMO from a .NET application through COM interop. For more information about SQL-DMO, see Microsoft SQL Server Books Online.

The ListAvailableSQLServers( ) method of the SQL-DMO Application object returns a NameList object that enumerates all running servers that listen on named pipes and are located in the same domain. Any servers running on Windows 9x will not be reported because they do not listen on named pipes. The discovery is based on a network broadcast, so if you are disconnected from a network, local servers will not be enumerated.

This procedure does not return desktop (MSDE) instances.