A home server is a server located in a private residence providing services to other devices inside or outside the household through a home network or the Internet. Such services may include file and printer serving, media center serving, web serving (on the network or Internet), web caching, account authentication and backup services. Because of the relatively low number of computers on a typical home network, a home server commonly does not require significant computing power and can be implemented with a re-purposed, older computer, or a plug computer. An uninterruptible power supply is sometimes used in case of power outages that can possibly corrupt data.
Services provided by home servers
Administration and configuration
Home servers often run headless, and can be administered remotely through a command shell, or graphically through a remote desktop system such as RDP, VNC, Webmin, Apple Remote Desktop, or many others.
Some home server operating systems (such as Windows Home Server) include a consumer-focused graphical user interface (GUI) for setup and configuration that is available on home computers on the home network (and remotely over the Internet via remote access). Others simply enable users to use native operating system tools for configuration.
Centralized storage
Home servers often act as network-attached storage (NAS) providing the major benefit that all users' files can be centrally and securely stored, with flexible permissions applied to them. Such files can be easily accessed from any other system on the network, provided the correct credentials are supplied. This also applies to shared printers.
Such files can also be shared over the Internet to be accessible from anywhere in the world using remote access.
Servers running Unix or Linux with the free Samba suite (or certain Windows Server products - Windows Home Server excluded) can provide domain control, custom logon scripts, and roaming profiles to users of certain versions of Windows. This allows a user to log on from any machine in the domain and have access to her or his "My Documents" and personalized Windows and application preferences - multiple accounts on each computer in the home are not needed.
Media serving
Home servers are often used to serve multi-media content, including photos, music, and video to other devices in the household (and even to the Internet; see Space shifting, Tonido and Orb). Using standard protocols such as DLNA or proprietary systems such as iTunes, users can access their media stored on the home server from any room in the house. Windows XP Media Center Edition, Windows Vista, and Windows 7 can act as a home server, supporting a particular type of media serving that streams the interactive user experience to Media Center Extenders including the Xbox 360.
A typical MythTV menu.
Windows Home Server supports media streaming to Xbox 360 and other DLNA-based media receivers via the built-in Windows Media Connect technology. Some Windows Home Server device manufacturers, such as HP, extend this functionality with a full DLNA implementation such as PacketVideo TwonkyMedia server.
There are many open-source and fully functional programs for media serving available for Linux. LinuxMCE is one example, which allows other devices to boot off a hard drive image on the server, allowing them to become appliances such as set-top boxes. Asterisk, Xine, MythTV (another media serving solution), VideoLAN, SlimServer, DLNA, and many other open-source projects are fully integrated for a seamless home theater/automation/telephony experience.
On an Apple Macintosh server, options include iTunes, PS3 Media Server, and Elgato. Additionally, for Macs directly connected to TVs, Boxee can act as a full-featured media center interface.
Servers are typically always on so the addition of a TV or radio tuner allows recording to be scheduled at any time.
Some home servers provide remote access to media and entertainment content.
Remote access
The Webmin Interface as it would appear in a standard web browser.
A home server can be used to provide remote access into the home from devices on the Internet, using remote desktop software and other remote administration software. For example, Windows Home Server provides remote access to files stored on the home server via a web interface as well as remote access to Remote Desktop sessions on PCs in the house. Similarly, Tonido provides direct access via a web browser from the Internet without requiring any port forwarding or other setup. Some enthusiasts often use VPN technologies as well.
On a Linux server, two popular tools are (among many) VNC and Webmin. VNC allows clients to remotely view a server GUI desktop as if the user was physically sitting in front of the server. A GUI need not be running on the server console for this to occur; there can be multiple 'virtual' desktop environments open at the same time. Webmin allows users to control many aspects of server configuration and maintenance all from a simple web interface. Both can be configured to be accessed from anywhere on the Internet.
Servers can also be accessed remotely using the command line-based Telnet and SSH protocols.
Web serving
Some users choose to run a web server in order to share files easily and publicly (or privately, on the home network). Others set up web pages and serve them straight from their home, although this may be in violation of some ISPs terms of service. Sometimes these web servers are run on a nonstandard port in order to avoid the ISP's port blocking. Example web servers used on home servers include Apache and IIS.
Many other web servers are available; see Comparison of lightweight web servers, Comparison of web servers.
Web proxy
Some networks have an HTTP proxy which can be used to speed up web access when multiple users visit the same websites, and to get past blocking software while the owner is using the network of some institution that might block certain sites. Public proxies are often slow and unreliable and so it is worth the trouble of setting up one's own private proxy.
Some proxies can be configured to block websites on the local network if it is set up as a transparent proxy.
Many home servers also run e-mail servers that handle e-mail for the owner's domain name. The advantages are having much bigger mailboxes and maximum message size than most commercial e-mail services. Access to the server, since it is on the local network is much faster than using an external service. This also increases security as e-mails do not reside on an off-site server.
BitTorrent
Home servers are ideal for utilizing the BitTorrent protocol for downloading and seeding files as some torrents can take days, or even weeks to complete and perform better on an uninterrupted connection. There are many text based clients such as rTorrent and web-based ones such as TorrentFlux and Tonido available for this purpose. BitTorrent also makes it easier for those with limited bandwidth to distribute large files over the Internet.
Gopher
An unusual service is the Gopher protocol, a hypertext document retrieval protocol which pre-dated the World Wide Web and was popular in the early 1990s. Many of the remaining gopher servers are run off home servers utilizing PyGopherd and the Bucktooth gopher server.
Home automation
Home automation requires a device in the home that is available 24/7. Often such home automation controllers are run on a home server.
Security monitoring
Relatively low cost CCTV DVR solutions are available that allow recording of video cameras to a home server for security purposes. The video can then be viewed on PCs or other devices in the house.
A series of cheap USB-based webcams can be connected to a home server as a makeshift CCTV system. Optionally these images and video streams can be made available over the Internet using standard protocols.
Family applications
Home servers can act as a host to family-oriented applications such as a family calendar, to-do lists, and message boards.
IRC and instant messaging
Because a server is always on, an IRC client or IM client running on it will be highly available to the Internet. This way, the chat client will be able to record activity that occurs even while the user is not at the computer, e.g. asleep or at work or school. Textual clients such as Irssi and tmsnc can be detached using GNU Screen for example, and graphical clients such as Pidgin can be detached using xmove. Quassel provides a specific version for this kind of use. Home servers can also be used to run personal XMPP servers and IRC servers as these protocols can support a large number of users on very little bandwidth
Online gaming
Some multiplayer games such as Continuum, Tremulous, Minecraft, and Doom have server software available which users may download and use to run their own private game server. Some of these servers are password protected, so only a selected group of people such as clan members or whitelisted players can gain access to the server. Others are open for public use and may move to colocation or other forms of paid hosting if they gain a large number of players.
Third-party platform
Home servers often are platforms that enable third-party products to be built and added over time. For example, Windows Home Server provides a Software Development Kit. Similarly, Tonido provides an application platform that can be extended by writing new applications using their SDK.
Operating systems
Home servers run many different operating systems. Enthusiasts who build their own home servers can use whatever OS is conveniently available or familiar to them, such as Microsoft Windows, Mac OS X, GNU/Linux, Solaris, BSD or Plan 9 from Bell Labs. Many people choose Linux because of its lower resource use, and therefore lower system requirements.
