As a supplement to Blindy's answer I wanted to mention that another way to configure the providers is to change the connection string settings of the default ConnectionString used by most of the providers, which is LocalSqlServer. To do this you just override that particular ConnectionString in your web.config like so:
<connectionStrings> <clear /> <add name="LocalSqlServer" connectionString="change this to be the details of your host database" providerName="System.Data.SqlClient" /> </connectionStrings>
Also, if you don't want to clear the entire connectionStrings section you can just remove the particular connection string like this:
<connectionStrings> <remove name="LocalSqlServer" /> <add name="LocalSqlServer" connectionString="change this to be the details of your host database" providerName="System.Data.SqlClient" /> </connectionStrings>
This works, because all providers that default to using Sql Server for their Data Store - such as the membership provider - use the "LocalSqlServer" connection string by default. Thus, if you override it, you don't have to change each provider to point to a different Connection String.
Also, for security reasons, you might want to look into encrypting the connectionString section of your web.config file. The following two articles provide more info.
Encrypting and Decrypting Configuration Sections
How To: Encrypt Configuration Sections in ASP.NET 2.0 Using RSA