Server appliance - AbsoluteAstronomy.com

A server appliance is a computer appliance

Computer appliance

A computer appliance is generally a separate and discrete hardware device with integrated software , specifically designed to provide a specific computing resource. These devices became known as "appliances" because of their similarity to home appliances, which are generally "closed and sealed" –...

that works as a server

Server (computing)

In the context of client-server architecture, a server is a computer program running to serve the requests of other programs, the "clients". Thus, the "server" performs some computational task on behalf of "clients"...

. It is designed so that the end-user

End-user

Economics and commerce define an end user as the person who uses a product. The end user or consumer may differ from the person who purchases the product...

does not need to understand the details of the operating system

Operating system

An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...

or the commands associated with it. Server appliances have their hardware and software preconfigured by the manufacturer. The appliance is plugged into an existing network

Computer network

A computer network, often simply referred to as a network, is a collection of hardware components and computers interconnected by communication channels that allow sharing of resources and information....

and is turned on by the end-user. The user selects the components to be active, through a simple user interface, and the appliance then boots to an active state, which is usable within minutes. Server appliances are designed to run and be controlled remotely after the initial set-up. The units are designed to be very easy to operate and provide narrow selection of network services.

Examples of server appliances include the Google Mini, a search appliance

Search appliance

A search appliance is a type of computer appliance which is attached to a corporate network for the purpose of indexing the content shared across that network in a way that is similar to a web search engine.-Architecture:...

designed for indexing corporate websites and returning these results, as well as the ASA Firewall

Cisco ASA

In computer networking, Cisco ASA 5500 Series Adaptive Security Appliances, or simply Cisco ASA 5500 Series, is Cisco's line of network security devices introduced in 2005, that succeeded three existing lines of popular Cisco products:...

, a security appliance

Security appliance

A security appliance is any form of server appliance that is designed to protect computer networks from unwanted traffic.-Types of security appliances:* Active devices block unwanted traffic...

designed to protect IP

Internet Protocol

The Internet Protocol is the principal communications protocol used for relaying datagrams across an internetwork using the Internet Protocol Suite...

networks from unwanted inbound traffic. or IBM's Lotus Foundations

Lotus Foundations

Lotus Foundations is a bundled small-business server solutions package by IBM. The package includes Lotus Domino, directory services, file management, firewall, backup, web hosting and various other productivity tools...

which is designed to offer IT infrastructure services for the small to midsize business.

Purpose

Server appliances, unlike other computer appliances, provide server-related services, such as: FTP, e-mail

E-mail

Electronic mail, commonly known as email or e-mail, is a method of exchanging digital messages from an author to one or more recipients. Modern email operates across the Internet or other computer networks. Some early email systems required that the author and the recipient both be online at the...

, DNS

Domain name system

The Domain Name System is a hierarchical distributed naming system for computers, services, or any resource connected to the Internet or a private network. It associates various information with domain names assigned to each of the participating entities...

, VPN, firewall

Firewall (computing)

A firewall is a device or set of devices designed to permit or deny network transmissions based upon a set of rules and is frequently used to protect networks from unauthorized access while permitting legitimate communications to pass....

and print spooling services. They also operate as a web server

Web server

Web server can refer to either the hardware or the software that helps to deliver content that can be accessed through the Internet....

or a NAS or SAN Storage Server.

Typical usage

A server appliance can be integrated into an existing network's infrastructure.

Server appliances are often used in situations where there is a lack of IT

Information technology

Information technology is the acquisition, processing, storage and dissemination of vocal, pictorial, textual and numerical information by a microelectronics-based combination of computing and telecommunications...

staff resource. This can include SME and branch networks where they may be no resource at all and corporate networks where use of an appliance can allow less qualified staff to help manage the network.

The initial network or configuration may be entered through touch pad/push buttons on the front of the units, via a serial/VGA console or is set by DHCP.

For further configuration and/or maintenance these devices usually offer access to the server appliance through an internal web server. These web servers may listen on a special port

Computer port (software)

In computer programming, port has a wide range of meanings.A software port is a virtual/logical data connection that can be used by programs to exchange data directly, instead of going through a file or other temporary storage location...

and not on the normal port 80 for security reasons.

The now unavailable Cobalt Networks

Cobalt Networks

Cobalt Networks was a maker of low-cost Linux-based servers. Founded in 1996 in Mountain View, California under the name Cobalt Microserver, the company pioneered easy-to-use server appliances featuring secure web user interfaces, designed for Internet service providers and small to medium sized...

RaQ series was previously purchased by ISPs who used them to sell hosting, FTP and/or email services to clients, giving them remote administrative access directly to the machine.

Server appliances can also be utilized for non-traditional IT network functions, such as for remote product support. An early example developed by Pratt & Whitney in 2001 in the aerospace industry is the Onboard Internet Microserver, which extends an http network into a complex product at the subsystem level, such as an aircraft, using an embedded micro-web server. It acts as the host and user interface between the subsystem's controller and both local and remote users, primarily for product support functions such as remotely collecting, processing, accessing and transferring of operational data, as well as onboard hosting of technical maintenance information for local operator access. They can also be used to facilitate two way communications between operators in the field and the factory through normal web server supported functions such as email, ftp, chat, or even VoIP and video, depending upon wireless communications speeds available. Devices such as these, when deployed in a clustered network architecture, known as Network Centric Product Support (NCPS), can create remote product support capabilities capable of being scaled to large fleets, where every product and its components become nodes in a supply chain supported network.

Some appliances especially Storage appliances are based on common-used but certified or recommended server-hardware. Usually hardware and software are sold together (example NexentaStor ZFS-storage appliance). But there are also non-commercial or free software alternatives to build a server-appliance on recommended but regular hardware like NexentaStor Community edition or the napp-it ZFS appliance based on a free server-os like NexentaCore, OpenIndiana or other Solaris-based Distros.

Purpose

Typical usage

See also

Further reading