Windows Home Server

Windows Home Server is a home server operating system from Microsoft. Announced on January 7, 2007 at the Consumer Electronics Show by Bill Gates, Windows Home Server is intended to be a solution for homes with multiple connected PCs to offer file sharing, automated backups, and remote access.[3][4] It is based on Windows Server 2003 SP2.[5]

Windows Home Server was released to manufacturing on July 16, 2007.

Features

* Centralized Backup - Allows backup up to 10 PCs,[6] using Single Instance Store technology to avoid multiple copies of the same file, even if that file exists on multiple PCs.[7]
* Health Monitoring - Can centrally track the health of all PCs on the network, including antivirus and firewall status.[7]
* File Sharing - Offers network shares for computers to store the files remotely, acting as a network-attached storage device. Separate categories are provided for common file types like Documents, Music, Pictures and Videos.[7] The files are indexed for fast searching.[8]
* Printer Sharing - Allows a centralized print server to handle print jobs for all users.[7]
* Previous Versions - Takes advantage of Volume Shadow Copy Services to take point in time snapshots that allow older versions of files to be recovered.[9]
* Headless Operation - No monitor or keyboard attached to the device itself, much like a firewall or router.[7]
* Remote administration - Provides a client UI to remotely perform administrative tasks. Also allows Remote Desktop connections to the server.[10]
* Remote Access Gateway - Allows access to any PC on the network from outside the home.[10]
* Media Streaming - Can stream media to a Xbox 360 or other devices supporting Windows Media Connect.[7]
* Data redundancy - Guards against a single drive failure by duplicating data across multiple drives.[7]
* Expandable Storage - Provides a unified single and easily expandable storage space, removing the need for drive letters.[7]
* Extensibility through Add-Ins - Add-Ins allow third-party developers to extend the features and functionality of the server. Add-Ins can be developed using the Windows Home Server SDK, to provide additional services to the client computers or work with the data already on the server. Add-Ins can also be ASP.NET applications, hosted in IIS 6 running on WHS.[8]

Home Server Console

While the underlying operating system is built on Windows Server 2003 SP2, the configuration interface is designed to be user friendly enough that it can be set up without prior knowledge of server administration. The configuration interface, called the Home Server Console, is delivered as an RDP application to remote PCs - while the application runs on the server itself, the UI is rendered on the remote system. The Home Server Console client application can be accessed from any Windows PC. The server itself requires no video card or peripherals; it is designed to require only an Ethernet card and at least one other Windows XP or Windows Vista PC.

Technology

Windows Home Server is built on the same codebase as Windows Server 2003 SP2. It includes almost all technologies found in Windows Server 2003 SP2 but has been limited in some areas to remove unneeded complexity or limit its uses. It also includes some new capabilities not found in Windows Server 2003 SP2:

Drive Extender

Windows Home Server Drive Extender is a file-based replication system that provides three key capabilities:[11]

* Multi-disk redundancy so that if any given disk fails, data is not lost
* Arbitrary storage expansion by supporting any type of hard disk drive (Serial ATA, USB, FireWire etc.) in any mixture and capacity
* A single folder namespace (no drive letters)

Users (specifically those who configure a family's home server) deal with storage at two levels: Shared Folders and Disks. The only concepts relevant regarding disks is whether they have been "added" to the home server's storage pool or not and whether the disk appears healthy to the system or not. This is in contrast with Windows' Logical Disk Manager which requires a greater degree of technical understanding in order to correctly configure a RAID array.

Shared Folders have a name, a description, permissions, and a flag indicating whether duplication (redundancy) is on or off for that folder.

If duplication is on for a Shared Folder (which is the default on multi-disk Home Server systems and not applicable to single disk systems) then the files in that Shared Folder are duplicated and the effective storage capacity is halved. However, in situations where a user may not want data duplicated (e.g. TV shows that have been archived to a Windows Home Server from a system running Windows Media Center), Drive Extender provides the capability to not duplicate such files if the server is short on capacity or manually mark a complete content store as not for duplication.

Computer Backup

Windows Home Server Computer Backup automatically backs up all of the computers in a home to the server using an image-based system that ensures point-in-time-based restoration of either entire PCs or specific files and folders.[12] This technology uses Volume Shadow Services (VSS) technology on the client computer to take an image based backup of a running computer. Because the backup operates on data at the cluster level, single instancing can be performed to minimize the amount of data that travels over the network and that will ultimately be stored on the home server. This single instancing gives the server the ability to store only one instance of data, no matter if the data originated from another computer, another file, or even data within the same file.

Remote Access
Web Interface showing the shared files UI
Web Interface showing the shared files UI

The system also offers an SSL secured web browser based interface over the Internet to the shared file stores.[13] The release version promises access to the web interface via a free Windows Live-provided URL. The web interface also allows the uploading to and downloading of files from the content stores.[10] However, there is a limit of 2 GB for a single batch of upload.[14]

The system also acts as an RDP gateway, allowing remote control over the internet of supported internal machines on the home network over the internet.[13][14] Currently supported systems are those which would normally support Remote Desktop: Windows XP Professional, Tablet and Media Center editions and Windows Vista Business and Ultimate editions. The web interface also supports embedding the Remote Desktop ActiveX control, to provide remote access to home computers from within the web interface directly. Remote sessions can also connect to the Home Server console to configure the server over the internet.[14]

Compatibility

Windows Home Server features integration with Windows XP and Windows Vista through a software installation. Files stored on Windows Home Server can also be available through a Windows share, opening compatibility to a wide variety of operating systems.

Windows x64 Systems (XP x64, Vista x64, 2003 x64) are currently not supported for backup with Windows Home Server, but Microsoft has stated support will be considered after Windows Home Server is released. Integration of the backup suite with Mac OS X's Time Machine is also being considered.

Minimum system requirements:

The following minimum specs are needed:

* 1.0 GHz Intel Pentium 3 (or equivalent) processor
* 512 MB RAM
* 80 GB internal hard drive as primary drive
* 100 Mbit/s wired Ethernet

Additionally, the following are required for installation of the operating system only

* Bootable DVD drive
* Display
* Keyboard and mouse

Dedicated devices will have the operating system pre-installed and may be supplied with a server recovery disk which reloads the OS over a network connection.

Pricing and Availability

Windows Home Server will be sold in boxes at retail stores in System Builder style.

It is possible to obtain a copy of the System Builder version using one of the following SKU's:

* English – CCQ-00015

* French – CCQ-00016

* German – CCQ-00017 / CCQ-00038

* Spanish – CCQ-00018

The pricing of this System Builder Version (OEM Version) is in mid $100 range.

File Corruption Problems

On 20 December 2007 Microsoft formally warned users that files saved directly to or edited on shares on a WHS device may become corrupted [15], an issue first acknowledged in October 2007 [16]. Files which use alternate data streams may be affected, files which are part of backup sets are not affected.