Microsoft Knowledge Base Article 311078 contains the following summary and introduction:

SUMMARY

With the Install from Media (IFM) feature in the Active Directory Installation Wizard, you can use a restored system state backup as the data source when you promote a Microsoft Windows Server 2003-based domain controller in an existing domain. When you use IFM to promote a domain controller, you gain important advantages over network-based promotions. These advantages include:

Reduced use of network resources when new domain controllers are promoted in an existing domain.
Faster sourcing of Active Directory directory service and global catalog data to a new domain controller.
Improved recovery of Windows Server 2003-based domain controllers after a hardware or a software failure.

INTRODUCTION

IFM promotions include the following four steps:

1. Installing a Windows Server 2003-based domain controller in each domain where you will be performing IFM promotions.
2. Performing a system state backup from a Windows Server 2003-based domain controller in each domain where you will be performing IFM promotions.
3. Restoring the system state backup to the local drive of each Windows Server 2003-based computer that you want to promote. The restored system state backup must be from a domain controller in the same domain that the new domain controller will be promoted in.
4. Promoting the domain controllers that you installed in step 1 by using the Active Directory Installation Wizard.

This article describes how to create and to restore system state backups for IFM promotions and how to perform an IFM promotion.

Note You must have administrative credentials to perform IFM promotions.