Editing Server (computing) (section)

== Hardware ==
[[File:Inside and Rear of Webserver.jpg|thumb|A [[19-inch rack|rack-mountable]] server with the top cover removed to reveal internal components]]

[[Computer hardware|Hardware]] requirement for servers vary widely, depending on the server's purpose and its software. Servers often are more powerful and expensive than the clients that connect to them.

The name server is used both for the hardware and software pieces. For the hardware servers, it is usually limited to mean the high-end machines although software servers can run on a variety of hardwares.

Since servers are usually accessed over a network, many run unattended without a [[computer monitor]] or input device, audio hardware and [[Universal Serial Bus|USB]] interfaces. Many servers do not have a [[graphical user interface]] (GUI).  They are configured and managed remotely. Remote management can be conducted via various methods including [[Microsoft Management Console]] (MMC), [[PowerShell]], [[Secure Shell|SSH]] and [[web browser|browser-based]] [[out-of-band management]] systems such as Dell's [[Dell DRAC|iDRAC]] or HP's [[HP Integrated Lights-Out|iLo]].

=== Large servers ===
Large traditional single servers would need to be run for long periods without interruption. [[Availability]] would have to be very high, making hardware reliability and durability extremely important. [[Mission-critical]] enterprise servers would be very [[Fault tolerance|fault tolerant]] and use specialized hardware with low [[failure rate]]s in order to maximize [[uptime]]. [[Uninterruptible power supply|Uninterruptible power supplies]] might be incorporated to guard against power failure. Servers typically include hardware [[Redundancy (engineering)|redundancy]] such as dual [[power supply|power supplies]], [[RAID]] [[hard disk|disk]] systems, and [[ECC memory]],<ref>{{cite web|url=http://www.cs.rochester.edu/~kshen/papers/usenix2010-li.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://www.cs.rochester.edu/~kshen/papers/usenix2010-li.pdf |archive-date=2022-10-09 |url-status=live|title="A Realistic Evaluation of Memory Hardware Errors and Software System Susceptibility". Usenix Annual Tech Conference 2010|author=Li|author2=Huang|author3=Shen|author4=Chu|year=2010|access-date=2017-01-30}}</ref> along with extensive [[Preboot Execution Environment|pre-boot]] memory testing and verification. Critical components might be [[hot swappable]], allowing technicians to replace them on the running server without shutting it down, and to guard against overheating, servers might have more powerful fans or use [[water cooling]]. They will often be able to be configured, powered up and down, or rebooted remotely, using [[out-of-band management]], typically based on [[Intelligent Platform Management Interface|IPMI]]. Server casings are usually [[rack unit|flat and wide]], and designed to be rack-mounted, either on [[19-inch rack]]s or on [[Open Rack]]s.

These types of servers are often housed in dedicated [[data centers]]. These will normally have very stable power and Internet and increased security. Noise is also less of a concern, but power consumption and heat output can be a serious issue. Server rooms are equipped with air conditioning devices.

{{gallery
|File:DL380sREAR.jpg|A [[server rack]] seen from the rear
|File:Wikimedia Foundation Servers-8055 08.jpg|[[Wikimedia Foundation]] servers as seen from the front
|File:Wikimedia Foundation Servers-8055 23.jpg|[[Wikimedia Foundation]] servers as seen from the rear
|File:Wikimedia Foundation Servers-8055 02.jpg|[[Wikimedia Foundation]] servers as seen from the rear
}}

=== Clusters ===
{{Main|Server farm}}
A ''server farm'' or ''server cluster'' is a collection of computer servers maintained by an organization to supply server functionality far beyond the capability of a single device. Modern [[data center]]s are now often built of very large clusters of much simpler servers,<ref>{{cite web|url=http://www.cnet.com/news/google-uncloaks-once-secret-server-10209580/|title=Google uncloaks once-secret server|publisher=CBS Interactive|work=CNET|access-date=2017-01-30}}</ref> and there is a collaborative effort, [[Open Compute Project]] around this concept.

=== Appliances ===
A class of small specialist servers called [[network appliance]]s are generally at the low end of the scale, often being smaller than common desktop computers.

=== Mobile ===
A mobile server has a portable form factor, e.g. a [[laptop]].<ref>{{cite web|url=http://www.eurocom.com/products/showroom/products_files/mobileserver/mobileserver.cfm|title=Mobile Server, Power to go, EUROCOM Panther 5SE|archive-url=https://web.archive.org/web/20130317041045/http://www.eurocom.com/products/showroom/products_files/mobileserver/mobileserver.cfm|archive-date=2013-03-17}}</ref> In contrast to large [[data center]]s or rack servers, the mobile server is designed for on-the-road or ''ad hoc'' deployment into emergency, disaster or temporary environments where traditional servers are not feasible due to their power requirements, size, and deployment time.<ref>{{cite web|url=http://www.notebookreview.com/default.asp?newsID=6833&news=Getax+X500+rugged+mobile+server+notebook|title=Mobile Server Notebook|date=27 January 2022}}</ref> The main beneficiaries of so-called "server on the go" technology include network managers, software or database developers, training centers, military personnel, law enforcement, forensics, emergency relief groups, and service organizations.<ref name="deskeng1">{{cite web|url=http://www.deskeng.com/articles/aaambz.htm|title=Server-caliber Computer Doubles as a Mobile Workstation|access-date=2020-02-08|archive-date=2016-03-03|archive-url=https://web.archive.org/web/20160303225722/http://www.deskeng.com/articles/aaambz.htm}}</ref> To facilitate portability, features such as the [[Computer keyboard|keyboard]], [[display device|display]], [[Battery (electricity)|battery]] ([[uninterruptible power supply]], to provide power redundancy in case of failure), and mouse are all integrated into the chassis.