how do i allow the the database server (which may be on a different server to the web server) be able to change without re-programming of the web application?

at the moment i have a global.asax:


Code:
<%@ Import Namespace="System.Net" %>
<script runat="server">
Sub Session_OnStart()
Session("conClasf") = _
"Data Source=localhost;Integrated Security=SSPI;" & _
"Initial Catalog=Database"
Try
Session("hostname") = _
Dns.GetHostByAddress(Request.UserHostAddress).HostName
Catch ex As Exception
Session("hostname") = Request.UserHostAddress
End Try
End Sub
</script>


?
bernie