Offline Domain Join
Windows 7 or Windows Server 2008 R2 computers can use the new feature called "Offline Domain Join". This process requires the Windows 7 or Windows Server 2008 R2. This step requires two steps: First the computer account is created or provisioned on the domain controller and the resulting information is stored in the metadata, and then this information is transferred to the joining computer. The workstation then performs the joining part without having the connectivity with the domain controller.
You need to use Djoin.exe on the domain controller to accomplish above. Please use Djoin.exe /? to see the syntaxes.
An example is given below:
Djoin.exe /provision /domain Name_Of_the_Domain_To_Be_Joined /machine Client_Computer_Name /savefileFile_Name.txt
If you need more information just type djoin /?