There is another definition of DAC in SQL Server – but this one is about the emergency DBA connection method, used when the server it too busy to get onto any other way.
DAC can be a life saver but has to be configured in advance. Luckily its a two minute job and I do it on all Production servers. and here’s how …
– Right click on server-name (in SSMS Object explorer), and choose facets.
– when the Facets box pops up select Surface Area Configuration in the top box.
– in the lower box set RemoteDacEnabled to True, and save with OK.
** TO USE IT **
– startup SSMS and ensure nothing is connected.
– click on “New Query”
– in the “Connect to Server” box prefix the Server Name with “admin: ”
– complete Authentication and click “Connect”
You should now be connected within a minimal safe-mode type environment. That is, with a blank Object Explorer pane.
** UPDATE 05 Mar 2015 **
To enable DAC on multiple servers (2005 and above) programmatically (via Registered Servers) use this …
Use master GO sp_configure 'remote admin connections', 1 GO RECONFIGURE GO