Question

Running SQL Server 2008 R2 and ASP.NET MVC 2 web application on the Virtual Server of big german hosting-provider.

I have a problem to connect to the SQL Server.

On localhost this connection string works fine:

 @"Data Source=LOCAL-HP;Initial Catalog=OnlineVertrag;Integrated Security=True";

I’m using a similar connection string on the server:

@"Data Source=MYSERVER\SQLEXPRESS;Initial Catalog=OnlineVertrag;Integrated Security=True";

but nothing happens over there.

Here is my project which I am trying to connect: http://www.hotcont.eu/OnlineVertrag/Home

Answer 1

Based on your comments, your SQL instance on the server has a username/password combination. You cannot use the integrated security connection for a SQL Server connection requiring SQL authentication.

Using the login information provided to you by your host, you should update your connection string to the following:

Server=MYSERVER\SQLEXPRESS;Database=OnlineVertrag;User Id=myUsername;
Password=myPassword;

Taken from ConnectionStrings.com

EDIT

Ok – I think I know what you are dealing with now. You have a virutal machine hosted on a large hosting provider -> meaning that you have control over the machine itself (aka Remote Desktop Management or something?)

The SQL connection string that I provided is for use with SQL server accounts -> meaning those that you actually create within SQL server itself. The SQL connection string that you provided uses the current logged in user’s user account information from Windows to connect to SQL.

So here is the disconnection between localhost and the virtual server. When you are running on localhost, I am going to assume that you are using the built in web server to Visual Studio or some equivalent. Most often, during debugging, the web application is running under the Logged in user of the machine – aka: you. You have permission to your own SQL database, thus no issue. BUT…when you deploy your web application to an IIS instance, the web application is no longer running as the logged in user, but rather the identity of the application pool that is your app is a member of. Typically this is something like NETWORKSERVICE.

You have three options available to you

1. Enable and use SQL user accounts for connection from your web application and your SQL server. If you choose to go this route, you will need to use the connection string I provided above.

2. Login to your SQL server and add the identity of your application pool to the Allowed Users of SQL server and your database.

3. Change your application pool’s identity to an actual user account on the server (BAD IDEA)

Most web applications go with the first option as it allows you do a few things such as create a distinct SQL user for each application that you host and as well as you can explicitly define permissions for the SQL user to each database that it may need access to (for instance, do not allow the SQL user to DROP tables).

EDIT 2

The way you are trying to connect sounds like it should be using the Shared Memory Protocol, but it might be trying to connect over TCP/IP. I forgot this earlier, but most installs of SQL are not setup to listen on the TCP/IP interface on first install. To check your configuration, click the start button (or orb or whatever Microsoft calls that now) -> All Programs -> Microsoft SQL Server 2008 -> Configuration Tools -> SQL Server Configuration Manager. This will open a new window with some options on the left hand side. Click the SQL Server Network Configuration. Ensure that TCP/IP and Shared Memory is set to enabled. If a 64 bit install, you should probably do this for both the SQL Server Network Configuration (32 bit) and the SQL Server Network Configuration

http://msdn.microsoft.com/en-us/library/ms191294.aspx