SQL Server DAC Administrator-only connection

The DAC is an abbreviation for dedicated Administrator Connect, a dedicated administrator connection channel that allows administrators to connect to data, diagnose problems, and troubleshoot when SQL Server is unable to connect to the system because of insufficient resources.

In fact, a long time ago knew the DAC this stuff, but has not tried to connect.

The following records the first time I connected through a DAC.

First, the first step is to open. SQL is as follows:

1 ' Show advanced Options ',12go34'remote admin connections  ',15Go

The second part is login:

Click on the link in the red box to pop up the login window, in the server name: input Admin:localhost will be an error! The right thing to do is click File->new->database Enginee Query and see the next figure.

SQL Server DAC Administrator-only connection