iSCSI also provides support for attachment of IBM Bladecenters.

In computing, iSCSI ( ), is an abbreviation of Internet Small Computer System Interface, an Internet Protocol ( IP )- based storage networking standard for linking data storage facilities.

Instead it is commonplace for a server to load its initial operating system from a TFTP server or local boot device, and then use iSCSI for data storage once booting from the local device has finished.

Most Intel Ethernet controllers for servers support iSCSI boot.

Typically, this happens in a kernel-resident device driver that uses the existing network card ( NIC ) and network stack to emulate SCSI devices for a computer by speaking the iSCSI protocol.

Software initiators are available for most popular operating systems and are the most common method of deploying iSCSI.

When a TOE is used rather than an HBA, the host processor still has to perform the processing of the iSCSI protocol layer itself, but the CPU overhead for that task is low.

iSCSI HBAs or TOEs are used when the additional performance enhancement justifies the additional expense of using an HBA for iSCSI, rather than using a software-based iSCSI client ( initiator ).

An iSCSI target is often a dedicated network-connected hard disk storage device, but may also be a general-purpose computer, since as with initiators, software to provide an iSCSI target is available for most mainstream operating systems.

Common deployment scenarios for an iSCSI target include:

A storage array usually provides distinct iSCSI targets for numerous clients.

Initiators treat iSCSI LUNs the same way as they would a raw SCSI or IDE hard drive ; for instance, rather than mounting remote directories as would be done in NFS or CIFS environments, iSCSI systems format and directly manage filesystems on iSCSI LUNs.

iSCSI imposes no rules or restrictions on multiple computers sharing individual LUNs ; it leaves shared access to a single underlying filesystem as a task for the operating system.

** somewhat less popular protocol dedicated for a specific solution: FICON / ESCON, iSCSI, HyperSCSI, ATA over Ethernet or InfiniBand

By using an iSCSI client on a Windows OS ( Microsoft has free iSCSI clients for their OS's ) and a Linux device with iSCSI support, you can create an iSCSI virtual drive ( hosted on a remote networked device ), format it as NTFS, and then store EFS folders and data on it.

This can take the form of iSCSI, FibreChannel, AoE, or any other device which can be presented under Linux as a block device shared by a number of nodes, for example a DRBD device.

For general data storage on an already-booted computer, any type of generic network interface may be used to access iSCSI devices.

However, a generic consumer-grade network interface is not able to boot a diskless computer from a remote iSCSI data source.

This is used to kick off the iSCSI remote boot process, using the booting network interface's MAC address to direct the computer to the correct iSCSI boot target.

An initiator typically serves the same purpose to a computer as a SCSI bus adapter would, except that instead of physically cabling SCSI devices ( like hard drives and tape changers ), an iSCSI initiator sends SCSI commands over an IP network.

In a data center or enterprise environment, an iSCSI target often resides in a large storage array, such as a EqualLogic, Nimble Storage, Isilon, NetApp filer, EMC NS-series, CX4, VNX, VNXe, VMAX or a HDS HNAS computer appliance.

Implementing these connection interfaces within the computer presents similar challenges to the networking interfaces ( indeed iSCSI runs over the network interface ), and similarly these can be removed from the blade and presented individually or aggregated either on the chassis or through other blades.

iSCSI, NFS, or CIFS are all commonly used protocols that are used to allow an external hard drive to use a network to send data to a computer system.

In computer storage, a logical unit number, or LUN, is a number used to identify a logical unit, which is a device addressed by the SCSI protocol or protocols which encapsulate SCSI, such as Fibre Channel or iSCSI.

For example a virtual network adapter is used with a virtual private network, while a virtual disk device is used with iSCSI.

Unlike traditional Fibre Channel, which requires special-purpose cabling, iSCSI can be run over long distances using existing network infrastructure.

By doing this iSCSI takes a popular high-performance local storage bus and emulates it over wide-area networks, creating a storage area network ( SAN ).

However, the performance of an iSCSI SAN deployment can be severely degraded if not operated on a dedicated network or subnet ( LAN or VLAN ).

In particular, iSCSI SANs allow entire disk arrays to be migrated across a WAN with minimal configuration changes, in effect making storage " routable " in the same manner as network traffic.

A separate DHCP server may be configured to assist interfaces equipped with network boot capability to be able to boot over iSCSI.

The physical or logical volumes accessed via block I / O may be devices internal to a server, directly attached via SCSI or Fibre Channel, or distant devices accessed via a storage area network ( SAN ) using a protocol such as iSCSI, or AoE.

In computing, the proposed Internet Storage Name Service ( iSNS ) protocol allows automated discovery, management and configuration of iSCSI and Fibre Channel devices ( using iFCP gateways ) on a TCP / IP network.

Because iSNS is able to emulate Fibre Channel fabric services and manage both iSCSI and Fibre Channel devices, an iSNS server can be used as a consolidated configuration point for an entire storage network.

Because the iSNS database stores naming and discovery information about both Fibre Channel and iSCSI devices, iSNS servers are able to store mappings of Fibre Channel devices to proxy iSCSI device images on the IP network.

In mid 2004 Evesham and FalconStor Software, Inc., a leading developer of network storage infrastructure software solutions, announced an OEM agreement to supply the UK market with FalconStor's iSCSI Storage Server for Windows Storage Server 2003 ( R ) ( iSCSI Storage Server ), with Evesham's SilverSTOR iSAN family of products.

Computer memory is communicating data ( transferred to / from ) external storage, typically through standard storage interfaces or networks ( e. g., fibre channel, iSCSI ).

Computer memory is communicating data ( transferred to / from ) external storage, typically through standard storage interfaces or networks ( e. g., fibre channel, iSCSI ).

By carrying SCSI commands over IP networks, iSCSI is used to facilitate data transfers over intranets and to manage storage over long distances.

iSCSI can be used to transmit data over local area networks ( LANs ), wide area networks ( WANs ), or the Internet and can enable location-independent data storage and retrieval.

Although iSCSI can communicate with arbitrary types of SCSI devices, system administrators almost always use it to allow server computers ( such as database servers ) to access disk volumes on storage arrays.

The iSCSI specification refers to a storage resource located on an iSCSI server ( more generally, one of potentially many instances of iSCSI storage nodes running on that server ) as a target.

" iSCSI target " should not be confused with the term " iSCSI " as the latter is a protocol and not a storage server instance.