Editing ISCSI (section)

===Target===
{{See also|SCSI target}}
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''.

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:

====Storage array====
In a data center or enterprise environment, an iSCSI target often resides in a large storage array. These arrays can be in the form of commodity hardware with [[free software|free-software]]-based iSCSI implementations, or as commercial products such as in [[StorTrends]], [[Pure Storage]], [[HP StorageWorks]], [[EqualLogic]], [[Tegile Systems]], [[Nimble storage]], [[IBM Storwize family]], [[Isilon]], [[NetApp filer]], [[Dell EMC]], [[Kaminario]], NS-series, CX4, VNX, VNXe, VMAX, [[Hitachi Data Systems]] HNAS, or Pivot3 vSTAC.

A storage array usually provides distinct iSCSI targets for numerous clients.<ref>[http://roc.cs.berkeley.edu/papers/inet-computing.pdf Architecture and Dependability of Large-Scale Internet Services] David Oppenheimer and David A. Patterson, Berkeley, ''IEEE Internet Computing'', September–October 2002.</ref>

====Software target====
{{See also|List of storage area network management systems}}

Nearly all modern mainstream server operating systems (such as [[BSD]], [[Linux]], [[Solaris (operating system)|Solaris]] or [[Windows Server]]) can provide iSCSI target functionality, either as a built-in feature or with supplemental software. Some specific-purpose operating systems implement iSCSI target support.

====Logical unit number====
{{Main|Logical unit number}}
In [[SCSI]] terminology, LU stands for ''logical unit'', which is specified by a unique ''[[logical unit number]]''. A LUN represents an individually addressable (logical) SCSI device that is part of a physical SCSI device (target). In an iSCSI environment, LUNs are essentially numbered disk drives. An initiator negotiates with a target to establish connectivity to a LUN; the result is an iSCSI connection that emulates a connection to a SCSI hard disk. 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 [[Network File System (protocol)|NFS]] or [[CIFS]] environments, iSCSI systems format and directly manage filesystems on iSCSI LUNs.

In enterprise deployments, LUNs usually represent subsets of large [[RAID]] disk arrays, often allocated one per client. 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.