File server - Citizendia

In computing, a file server is a computer attached to a network that has the primary purpose of providing a location for the shared storage of computer files (such as documents, sound files, photographs, movies, images, databases, et cetera) that can be accessed by the workstations that are attached to the computer network. Computing is usually defined like the activity of using and developing Computer technology Computer hardware and software. A computer file is a block of Arbitrary Information, or resource for storing information which is available to a Computer program and is usually A computer network is a group of interconnected Computers. Networks may be classified according to a wide variety of characteristics The term server highlights the role of the machine in the client-server scheme, where the clients are the workstations using the storage. The client-server Software architecture model distinguishes client systems from server systems which communicate over a Computer network A file server is usually not performing any calculations, and does not run any programs on behalf of the clients. It is designed primarily to enable the rapid storage and retrieval of data where the heavy computation is provided by the workstations.

1 History of file servers
2 Types of file servers
3 Design of file servers
4 See also

History of file servers

In the mid-1980s enterprises became increasingly interested in ways to connect a rapidly growing population of personal computers. A personal computer ( PC) is any Computer whose original sales price size and capabilities make it useful for individuals and which is intended to be operated Novell proposed an approach using software to connect each workstation to a network file server that would manage both the network and access to network resources. Novell Inc ( is a global Software Corporation based in the United States specializing in enterprise operating systems such as SUSE At the same time 3Com Corporation was creating Ethernet adapter cards, building hardware connectivity needed for such approach. Ethernet is a family of frame -based Computer networking technologies for Local area networks (LANs

Novell grew upon the strength of its Netware operating system, used for file serving, and by the late 1980s had a 50% market share of local area networks. NetWare is a Network operating system developed by Novell Inc Seeing the potential growth in this arena IBM and Microsoft both introduced their own file server strategies. International Business Machines Corporation abbreviated IBM and nicknamed "Big Blue", is a multinational Computer Technology Microsoft Corporation is an American multinational Computer technology Corporation, which rose to dominate the Home computer

Twenty years after its peak, Novell and 3Com have virtually disappeared from the Server market; today disk servers (a NAS or a SAN) supplied by one of the leading vendors such as EMC or NetApp are typically attached to a file server running the Microsoft Windows or Linux operating systems. Large data centers, that serve millions of customers (such as Google's), run server farms on specialized equipment with proprietary operating systems. A data center is a facility used to house computer systems and associated components such as telecommunications and storage systems Google Inc is an American public corporation, earning revenue from advertising related to its Internet search, e-mail, online A server farm or server cluster is a collection of Computer servers usually maintained by an enterprise to accomplish server needs far beyond the capability

Types of file servers

A file server may be dedicated or non-dedicated. A dedicated server is generally designed specifically for use as a file server, with workstations attached for reading and writing files and databases. A workstation may share files with other workstations on the network directly however by turning on its "Server" service and then by creating a "Share" -- this process creates a non-dedicated file server that is primarily being used as a workstation.

File servers may also be categorized by the method of access: Internet file servers are frequently accessed by File Transfer Protocol (FTP) or by HTTP (but are different from web servers, that often provide dynamic web content in addition to static files). The term web server can mean one of two things A Computer program that is responsible for accepting HTTP requests from web clients which are Servers on a LAN are usually accessed by SMB/CIFS protocol (Windows and Unix-like) or NFS protocol (Unix-like systems). In Computer networking, Server Message Block ( SMB) operates as an application-level network protocol mainly used to provide Shared access In Computer networking, Server Message Block ( SMB) operates as an application-level network protocol mainly used to provide Shared access Microsoft Windows is a series of Software Operating systems and Graphical user interfaces produced by Microsoft. A Unix-like (sometimes shortened to *nix) Operating system is one that behaves in a manner similar to a Unix system while not necessarily conforming Database servers, that provide access to a shared database via a database device driver, are not regarded as file servers. A database server is a Computer program that provides Database services to other computer programs or Computers as defined by the Client-server Most file servers are simultaneously print servers too, as they provide access to printers via network. A print server, or printer server, is a computer or device that is connected to one or more printers and to client computers over a network, and A single file serving computer may be accessible by multiple means: it may run an FTP server, an CIFS server, etc. , serving the same files.

Design of file servers

In modern businesses the design of file servers is complicated by competing demands for storage space, access speed, recoverability, ease of administration, security, and budget. In Databases and Transaction processing, a schedule (transaction history is Serializable, has the Serializability property if its Security is the condition of being protected against danger loss and criminals This is further complicated by a constantly changing environment, where new hardware and technology rapidly obsoletes old equipment, and yet must seamlessly come online in a fashion compatible with the older machinery. To manage throughput, peak loads, and response time, vendors may utilize queuing theory^[1] to model how the combination of hardware and software will respond over various levels of demand. In Communication networks, such as Ethernet or Packet radio, throughput is the average rate of successful message delivery over a communication channel A vendor or a supplier is a Supply chain management term meaning anyone who provides goods or services to a company Servers may also employ dynamic load balancing scheme to distribute requests across various pieces of hardware.

The primary piece of hardware equipment for servers over the last couple of decades has proven to be the hard disk drive. A hard disk drive ( HDD) commonly referred to as a hard drive, hard disk, or fixed disk drive, is a Non-volatile storage device Although other forms of storage are viable (such as magnetic tape and RAM) disk drives have continued to offer the best fit for cost, performance, and capacity. Magnetic tape is a medium for Magnetic recording generally consisting of a thin magnetizable coating on a long and narrow strip of Plastic.

Storage

Since the crucial function of a file server is storage, hardware has been developed to operate multiple disk drives together as a team, forming a disk array. A disk array is a Disk storage system which contains multiple Disk drives It is differentiated from a Disk enclosure, in that an array has Cache A disk array typically has cache (temporary memory storage that is faster than the magnetic disks), as well as advanced functions like RAID and storage virtualization. In Computer science, a cache (kæʃ like "cash") is a collection of data duplicating original RAID — which stands for Redundant Array of Inexpensive Disks,or alternatively Redundant Array of Independent Disks (a less specific name and thus now the Storage virtualization refers to the process of abstracting logical storage from physical storage. Typically disk arrays increase level of availability by using redundant components other than RAID, such as power supplies. In Telecommunications and Reliability theory, the term availability has the following meanings 1 Power supply is a reference to a source of Electrical power. A device or system that supplies Electrical or other types of Energy to an output load Disk arrays may be consolidated or virtualized in a storage area network (SAN). In Information technology, a storage area network ( SAN) is an architecture to attach remote computer storage devices (such as Disk arrays tape libraries

Filers

In 1990s, introduction of specialized file serving devices, the NetApp filers, popularized the concept of network-attached storage (NAS). In Computer storage, NetApp filer, known also as NetApp Fabric-Attached Storage ( FAS) is NetApp 's Network attached storage (NAS Network-attached storage ( NAS) is file-level Computer data storage connected to a Computer network providing data access to heterogeneous network clients To this time, file servers were still implemented with general-purpose servers and OSes. NetApp changed this with introducing specialized network appliances, with a proprietary software and scalable to multiple disk enclosures holding tens or hundreds of disks grouped in multiple disk arrays. A Computer Appliance is generally a separate and discrete hardware component specifically designed to provide a specific compute resource and which often resides on a dedicated hardware In Telecommunications and Software engineering, scalability is a desirable property of a system a network or a process which indicates its ability to either Filers later extended to non-file protocols, such as iSCSI, but still NAS is popularly perceived as mainly a file serving technology. In computing the iSCSI (for " Internet SCSI " protocol allows clients (called initiators) to send SCSI commands ( ''CDBs''

Security

File servers generally offer some form of system security to limit access to files to specific users or groups. In large organizations, this is a task usually delegated to what is known as directory services such as openLDAP, Novell's eDirectory or Microsoft's Active Directory. In software engineering a directory is similar to a dictionary it enables the look up of a name and information associated with that name OpenLDAP Software is a free, Open source implementation of the Lightweight Directory Access Protocol (LDAP developed by the OpenLDAP Project Novell eDirectory (formerly called Novell Directory Services, NDS) is an X Active Directory ( AD) is a technology created by Microsoft that provides a variety of network services including LDAP -like Directory

These servers work within the hierarchical computing environment which treat users, directories, computers, applications and files as distinct but related entities on the network and grant access based on user or group credentials. In many cases, the directory service spans many file servers, potentially hundreds for large organizations. In the past, and in smaller organizations, authentication can take place directly to the server itself.

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