VirtualBox network blues

If it happen to you like me and you install the latest VirtualBox version on Windows 7. Setup is running smoothly and everything looks fine. But when you try something like the docker toolbox and all you get some strange errors. This could point to a problem with the network stack.

In this case remove your current installation and do a restart. Now start the install, e.g. via "Run" like this:

VirtualBox-x.x.x-yyyyy-Win.exe -msiparams NETWORKTYPE=NDIS5

This tells the installer to use the older version of the VirtualBox network stack. Using this the docker toolbox works like charm.

Windows 10 Remote Desktop Via RD Gateway fails

Using Windows 10 there was a problem using the remote desktop client to connect to my company windows machine. It was not possible to get beyond the remote desktop gateway. All I got was: "Your computer can't connect to the remote server because the Remote Desktop Gateway server is temporarily unavailable. Try connecting later or contact your network administrator for assistance."

But today I found that workaround at: https://social.technet.microsoft.com/Forums/windowsserver/en-US/58521677-b54c-4285-9a06-9a966a9d8549/clean-install-windows-10-can-not-rdp-via-2012-rd2-rdg?forum=winserverTS

Long story short:

Add this using regedit:

HKEY_CURRENT_USER\Software\Microsoft\Terminal Server Client
Name: RDGClientTransport
Type: Dword
Data: 1

Restart all running mstsc.exe instances and everything should work as expected.

Entity Framework on system databases

Entity Framework supports code only entity models. The default behavior is to deploy this model to the connected database. If you want to access system databases this is unacceptable. Fortunately this can be disabled. Unfortunately it's not easy. You have to implement an custom database initialization strategy. The following example is adding an check if the code model is compatible with the current database.

private class DatabaseInitializer : IDatabaseInitializer<SqlServerCatalog>
{

    public void InitializeDatabase(SqlServerCatalog context)
    {
        if (!context.Database.CompatibleWithModel(false))
            throw new Exception("");
    }
}

Now you habe to override the static constructor of your implementation of the DbContext class:

static YourDBContext()
{
    System.Data.Entity.Database.SetInitializer<YourDBContext>(new DatabaseInitializer());
}

Docker easy with fig

Playing with Docker is easy. More easy using fig. [http://www.fig.sh/] It's very easy to create an configuration file stating all required dockerized services. The services can be easily linked by name. E.g. if you need a Zookeeper instance for one or multiple Kafka instances. [https://github.com/wurstmeister/kafka-docker/blob/master/fig.yml] The company behind is orchard laboratories. It provides cloud based docker hosts. The company was acquired by the Docker Inc. in July 2014.

Active Directory user rename and SQL Server

Renaming users is easy. Spreading the news about it is hard. Especially the SQL Server is ignorant about changes. All security tokens for an user or group is cached for Performance reasons. The only way to force an update is to drop the existing cache using: DBCC FREESYSTEMCACHE ('TokenAndPermUserStore')


Format data types on SQL Server 2012+

I was required to format multiple variables and concat them into a beautiful string. I stumbled upon the FORMAT function. A build-in function since SQL Server 2012.Look at http://msdn.microsoft.com/en-us/library/hh213505(v=sql.110).aspx

Missed the part that states:

The following table lists the acceptable data types for the value argument together with their .NET Framework mapping equivalent types.

They are serious about this. Tried the bit data type and it failed miserably.
So you still have to do a

 convert([n]varchar(1), @bit_value)  

for the value as number or

 case when @bit_value = 1 then 'TRUE' when @bit_value = 0 then 'FALSE' else 'NULL' end  

for the value as text.