Windows Server 2008

Default user interface for Server Core. Because Server Core does not include a shell, programs such as Notepad use an embedded file dialog inherited from Windows 3.x/Windows NT 3.1.

Windows Server 2008 includes a variation of installation called Server Core. Server Core is a significantly scaled-back installation where no Windows Explorer shell is installed. It also lacks .NET Framework, Internet Explorer, Windows PowerShell, and many other non-essential features. All configuration and maintenance is done entirely through command-line interface windows, or by connecting to the machine remotely using Microsoft Management Console (MMC). Notepad and some Control Panel applets, such as Regional Settings, are available.

A Server Core installation can be configured for several basic roles, including the domain controller (Active Directory Domain Services), Active Directory Lightweight Directory Services (formerly known as Active Directory Application Mode[13]), DNS Server, DHCP server, file server, print server, Windows Media Server, Internet Information Services 7 web server and Hyper-V virtual server roles. Server Core can also be used to create a cluster with high availability using failover clustering or network load balancing.

Andrew Mason, a program manager on the Windows Server team, noted that a primary motivation for producing a Server Core variant of Windows Server 2008 was to reduce the attack surface of the operating system, and that about 70% of the security vulnerabilities in Microsoft Windows from the prior five years would not have affected Server Core.[14]

The Active Directory domain functionality that was retained from Windows Server 2003 was renamed to Active Directory Domain Services (ADDS).[15]

• Active Directory Federation Services (ADFS) enables enterprises to share credentials with trusted partners and customers, allowing a consultant to use their company user name and password to log in on a client's network.
• Active Directory Lightweight Directory Services (AD LDS), (formerly Active Directory Application Mode, or ADAM)
• Active Directory Certificate Services (ADCS) allow administrators to manage user accounts and the digital certificates that allow them to access certain services and systems. Identity Integration Feature Pack is included as Active Directory Metadirectory Services.
• Active Directory Rights Management Services (ADRMS)
• Read-only domain controllers (RODCs), intended for use in branch office or other scenarios where a domain controller may reside in a low physical security environment. The RODC holds a non-writeable copy of Active Directory, and redirects all write attempts to a full domain controller. It replicates all accounts except sensitive ones.[16] In RODC mode, credentials are not cached by default. Also, local administrators can be designated to log on to the machine to perform maintenance tasks without requiring administrative rights on the entire domain.[17]
• Restartable Active Directory allows ADDS to be stopped and restarted from the Management Console or the command-line without rebooting the domain controller. This reduces downtime for offline operations and reduces overall DC servicing requirements with Server Core. ADDS is implemented as a Domain Controller Service in Windows Server 2008.
• All of the Group Policy improvements from Windows Vista are included. Group Policy Management Console (GPMC) is built-in. The Group Policy objects are indexed for search and can be commented on.[18]
• Policy-based networking with Network Access Protection, improved branch management and enhanced end user collaboration. Policies can be created to ensure greater Quality of Service for certain applications or services that require prioritization of network bandwidth between client and server.
• Granular password settings within a single domain - ability to implement different password policies for administrative accounts on a "group" and "user" basis, instead of a single set of password settings to the whole domain.

Windows Server 2008 offers high availability to services and applications through Failover Clustering. Most server features and roles can be kept running with little to no downtime.

In Windows Server 2008, the way clusters are qualified changed significantly with the introduction of the cluster validation wizard.[19] The cluster validation wizard is a feature that is integrated into failover clustering in Windows Server 2008. With the cluster validation wizard, an administrator can run a set of focused tests on a collection of servers that are intended to use as nodes in a cluster. This cluster validation process tests the underlying hardware and software directly, and individually, to obtain an accurate assessment of how well failover clustering can be supported on a given configuration.

This feature is only available in Enterprise and Datacenter editions of Windows Server.

• The ability to resize hard disk partitions without stopping the server, even the system partition. This applies only to simple and spanned volumes, not to striped volumes.
• Shadow Copy based block-level backup which supports optical media, network shares and Windows Recovery Environment.
• DFS enhancements - SYSVOL on DFS-R, Read-only Folder Replication Member. There is also support for domain-based DFS namespaces that exceed the previous size recommendation of 5,000 folders with targets in a namespace.[20]
• Several improvements to Failover Clustering (high-availability clusters).[21]
• Internet Storage Naming Server (iSNS) enables central registration, deregistration and queries for iSCSI hard drives.
• Self-healing NTFS: In Windows versions prior to Windows Vista, if the operating system detected corruption in the file system of an NTFS volume, it marked the volume "dirty"; to correct errors on the volume, it had to be taken offline. With self-healing NTFS, an NTFS worker thread is spawned in the background which performs a localized fix-up of damaged data structures, with only the corrupted files/folders remaining unavailable without locking out the entire volume and needing the server to be taken down. S.M.A.R.T. detection techniques were added to help determine when a hard disk may fail.[22]

Hyper-V architecture

Hyper-V is hypervisor-based virtualization software, forming a core part of Microsoft's virtualization strategy. It virtualizes servers on an operating system's kernel layer. It can be thought of as partitioning a single physical server into multiple small computational partitions. Hyper-V includes the ability to act as a Xen virtualization hypervisor host allowing Xen-enabled guest operating systems to run virtualized.[23] A beta version of Hyper-V shipped with certain x86-64 editions of Windows Server 2008, prior to Microsoft's release of the final version of Hyper-V on 26 June 2008 as a free download. Also, a standalone variant of Hyper-V exists; this variant supports only x86-64 architecture.[24] While the IA-32 editions of Windows Server 2008 cannot run or install Hyper-V, they can run the MMC snap-in for managing Hyper-V.

Windows System Resource Manager (WSRM) is integrated into Windows Server 2008. It provides resource management and can be used to control the amount of resources a process or a user can use based on business priorities. Process Matching Criteria, which is defined by the name, type or owner of the process, enforces restrictions on the resource usage by a process that matches the criteria. CPU time, bandwidth that it can use, number of processors it can be run on, and allocated to a process can be restricted. Restrictions can be set to be imposed only on certain dates as well.

Server Manager is a new roles-based management tool for Windows Server 2008.[25] It is a combination of Manage Your Server and Security Configuration Wizard from Windows Server 2003. Server Manager is an improvement of the Configure my server dialog that launches by default on Windows Server 2003 machines. However, rather than serve only as a starting point to configuring new roles, Server Manager gathers together all of the operations users would want to conduct on the server, such as, getting a remote deployment method set up, adding more server roles etc., and provides a consolidated, portal-like view about the status of each role.[26]

• Support for 128- and 256-bit AES encryption for the Kerberos authentication protocol.
• New cryptography (CNG) API which supports elliptic curve cryptography and improved certificate management.
• Secure Socket Tunneling Protocol, a new Microsoft proprietary VPN protocol.
• AuthIP, a Microsoft proprietary extension of the IKE cryptographic protocol used in IPsec VPN networks.
• Server Message Block 2.0 protocol in the new TCP/IP stack provides a number of communication enhancements, including greater performance when connecting to file shares over high-latency links and better security through the use of mutual authentication and message signing.

• Fully componentized operating system.
• Improved hot patching, a feature that allows non-kernel patches to occur without the need for a reboot.
• Support for being booted from Extensible Firmware Interface (EFI)-compliant firmware on x86-64 systems.
• Dynamic Hardware Partitioning supports hot-addition or replacement of processors and memory, on capable hardware.
• Windows Deployment Services (WDS) replacing Automated Deployment Services Windows Server 2008 home entertainment and Remote Installation Services. Windows Deployment Services supports an enhanced multicast feature when deploying operating system images.[27]
• Internet Information Services 7 - Increased security, Robocopy deployment, improved diagnostic tools, delegated administration.
• Windows Internal Database, a variant of SQL Server Express 2005, which serves as a common storage back-end for several other components such as Windows System Resource Manager, Windows SharePoint Services and Windows Server Update Services. It is not intended to be used by third-party applications.
• An optional "desktop experience" component provides the same Windows Aero user interface as Windows Vista, both for local users, as well as remote users connecting through Remote Desktop.

Due to the operating system being based on the same codebase as Windows Vista and being released on the same day as the initial release of Windows Vista Service Pack 1, the RTM release of Windows Server 2008 already includes Service Pack 1.

Service Pack 2 was initially announced on October 24, 2008[38] and released on May 26, 2009. Service Pack 2 added new features, such as Windows Search 4.0, support for Bluetooth 2.1, the ability to write to Blu-ray discs, and simpler Wi-Fi configuration. Windows Server 2008 specifically received the final release of Hyper-V 1.0, improved backwards compatibility with Terminal Server license keys and an approximate 10% reduction in power usage with this service pack.[39]

Windows Vista and Windows Server 2008 share the same service pack update binary because the codebases of the two operating systems are unified - Windows Vista and Windows Server 2008 are the first Microsoft client and server operating systems to share the same codebase since the release of Windows 2000.[40] The predecessors to Windows Vista and Windows Server 2008, Windows XP and Windows Server 2003, had unique codebases that used their own updates and service packs.

On October 27, 2009, Microsoft released the Platform Update for Windows Server 2008 and Windows Vista. It backports several APIs and libraries introduced in Windows Server 2008 R2 and Windows 7 to Windows Server 2008 and Windows Vista, including the Ribbon API, DirectX 11, the XPS library, the Windows Automation API and the Portable Device Platform.[41] A supplemental update was released in 2011 to provide improvements and bug fixes.[42]

Windows Server 2008 shipped with Internet Explorer 7, the same version that shipped with Windows Vista. The latest compatible version of the browser with Windows Server 2008 is Internet Explorer 9, released in 2011. Internet Explorer 9 was continually updated with cumulative monthly update rollups until support for Windows Server 2008 ended on January 14, 2020.[43]

The latest supported version of the .NET Framework officially is version 4.6, released on October 15, 2015.[44]

In July 2017, Microsoft released an update to add TLS 1.1 and 1.2 support to Windows Server 2008, however it is disabled by default after installing the update.[45]

Starting in March 2019, Microsoft began transitioning to exclusively signing Windows updates with the SHA-3 algorithm. As a result of this Microsoft released several updates throughout 2019 to add SHA-2 signing support to Windows Server 2008.[46]

In June 2018, Microsoft announced that they would be moving Windows Server 2008 to a monthly update model beginning with updates released in September 2018[47] - two years after Microsoft switched the rest of their supported operating systems to that model.[48]

With the new update model, instead of updates being released as they became available, only two update packages were released on the second Tuesday of every month until Windows Server 2008 reached its end of life - one package containing security and quality updates, and a smaller package that contained only the security updates. Users could choose which package they wanted to install each month. Later in the month, another package would be released which was a preview of the next month’s security and quality update rollup.

Installing the preview rollup package released for Windows Server 2008 on March 19, 2019, or any later released rollup package, will update the operating system kernel’s build number from version 6.0.6002 to 6.0.6003. This change was made so Microsoft could continue to service the operating system while avoiding “version-related issues”.[49]

The last non-extended security update rollup packages were released on January 14, 2020, the last day that Windows Server 2008 had extended support.[50]

Windows Server 2008 is eligible for the Extended Security Updates program. This program allows volume license customers to purchase, in yearly installments, security updates for the operating system until at most January 10, 2023. The licenses are paid for on a per-machine basis. If a user purchases an Extended Security Updates license in a later year of the program, they must pay for any previous years of Extended Security Updates as well. Extended Security Updates are released only as they become available.[51]