Deploying Windows Server 2003 Using ADS
Recently, we completed our series of articles that examined different methods of handling Windows XP deployments. We focused primarily on solutions that offered an increased degree of automation, centralized management, and auditing and reporting functionality. The need for technology that can install client operating systems on multiple computers is common, and products that address these needs come in handy in environments of practically any size. If you're in the process of installing Windows Server 2003, being familiar with Automated Deployment Services is critical.
However, the need for equivalent functionality for installing server operating system is also desired. However, the customer base, which consists primarily of larger enterprises, is smaller. While such capability is available as part of Remote Installation Services, this solution has been designed with desktop rollouts in mind and lacks centralized management, efficiency, and scalability features all of which are critical when dealing with servers. Microsoft addresses these challenges in the form of Automated Deployment Services, which is the topic of this article.
Automated Deployment Services (ADS) is a free add-on to Windows 2003 Server Enterprise Edition. Intended mainly for corporate clients and boasting hundreds and thousands of devices hosted in the data centers, ADS streamlines and automates deployment and maintenance of the recent server operating systems (covering 32-bit versions of Windows 2000 Standard and Advanced Server as well as Windows 2003 Standard, Web, and Enterprise Editions). It distances itself from other, similar solutions, such as Remote Installation Services, through a variety of significant functionality, scalability, manageability, and security enhancements, such as:
- Centralized deployment methodology designed to minimize the amount of time necessary to install and fully configure a new Windows server system. The initial investment in time and resources necessary to set up ADS can be easily justified in larger environments, with few variations in the way systems are set up. This makes it well-suited for blade servers.
- Leveraging Preboot Execution Environment (PXE) combined with Windows Preinstallation Environment (Windows PE) 2005 or its new ADS-specific alternative (Deployment Agent) for remote server installation on bare-metal hardware and virtual floppy operations (such as BIOS upgrades or RAID configurations).
- Remote operating system management and automation capabilities based on variety of administrative tools, from Microsoft Management Console snap-ins and command-line utilities to Windows Management Instrumentation-based scripts and programs.
- Efficient management through set-based operations targeting groups of devices, which can be referenced as a single entity.
- Set of innovative proprietary imaging tools, with built-in compression, defragmentation, encryption, simplified edits, and image library management.
- Bandwidth savings through multicasting support and bandwidth throttling.
- A complete audit of administrative tasks (facilitated by centralized operations and logging) with records stored in a SQL Server database.
From an architectural point of view, ADS forms an agent-based, centralized infrastructure. Its central piece is Controller Service system, which serves as a functional and communication hub for all operations. This includes interaction with two types of agents running on managed devices (Deployment and Administration), providing entry point for creating and scheduling administrative tasks (management tools require connection to the Controller Service), maintaining SQL Server-based database of all devices within its management scope (identified by MAC addresses of their network adapters or by their SMBIOS GUID), and coordinating two supplementary services responsible for carrying out its requests:
Network Boot Service
Network Boot Service (NBS) consists of three subcomponents, PXE Service, TFTP Service, and Deployment Agent Builder Service. It functions like an enhanced version of the Remote Installation Services server. It also relies on Microsoft DHCP Server for some of its features.
NBS' main purpose is facilitating remote operations on PXE-enabled (version 0.99c or later) devices without relying on their operating system. DHCP-initiated sessions established at the boot time on such devices serve as means for exchanging information necessary for the operating system installation and Virtual-Floppy-based activities. This includes network address of the system where PXE Service resides (provided by the server) and PNP identifiers of hardware components on the target device (provided by the client).
Depending on the instructions from its administrator, NBS might initiate operating system installation by downloading (using TFTP service) a copy of Windows Preinstallation Environment 2005. However, since Windows PE is not included with ADS, it is sold separately. For more information on this subject, refer to our earlier article in this series or ADS Deployment Agent created dynamically by Deployment Agent Builder Service and the required drivers (based on the device records stored in the SQL Server database), and rebooting the device. Another potential action NBS can be triggered is a system boot using Virtual Floppy image (created with ADS DskImage utility and downloaded via TFTP Service), which facilitates the need for BIOS and firmware upgrades, RAID configuration, or similar types of operations. In the past they have required direct access to the hardware to perform a floppy-based boot.