SAN

The SAN configuration screen allows you to connect your appliance to your SAN (Storage Area Network). A SAN is made up of three basic components:

A client which will access the storage on the network
A storage appliance which will provide the storage on the network
A network to link the client to the storage

These three components remain the same regardless of which protocol is used on the network. In some cases, the network may even be a cable between the initiator and the target, but in most cases, there is some type of switching involved.

Terminology

To configure the appliance to operate on a SAN, it is essential to understand some basic terms:

Term	Description
Logical Unit	A term used to describe a component in a storage system. Uniquely numbered, this creates what is referred to as a Logicial Unit Number, or LUN. A storage system, being highly configurable, may contain many LUNs. These LUNs, when associated with one or more SCSI targets, forms a unique SCSI device, a device that can be accessed by one or more SCSI initiators.
Target	A storage system end-point that provides a service of processing SCSI commands and I/O requests from an initiator. A target is created by the storage system administrator, and is identified by unique addressing methods. A target, once configured, consists of zero or more logical units.
Target group	A set of targets. LUNs are exported over all the targets in one specific target group.
Initiator	An application or production system end-point that is capable of initiating a SCSI session, sending SCSI commands and I/O requests. Initiators are also identified by unique addressing methods.
Initiator group	A set of initiators. When an initiator group is associated with a LUN, only initiators from that group may access the LUN. As of the 2013.1.0 software release, a LUN can be associated with multiple initiator groups.

Additionally, it is important to be aware of SCSI transport protocols:

Term	Description
FC	Fibre Channel, a protocol for sharing SCSI based storage over a storage area network (SAN), consisting of fiber-optic cables, FC switches and HBAs.
iSCSI	Internet SCSI, a protocol for sharing SCSI based storage over IP networks.
iSER	iSCSI Extension for RDMA, a protocol that maps the iSCSI protocol over a network that provides RDMA services (i.e. InfiniBand). The iSER protocol is transparently selected by the iSCSI subsystem, based on the presence of correctly configured IB hardware. In the CLI and BUI, all iSER-capable components (targets and initiators) are managed as iSCSI components.
SRP	SCSI RDMA Protocol, a protocol for sharing SCSI based storage over a network that provides RDMA services (i.e. InfiniBand).

Targets and Initiators

Targets and initiators are configured by protocol. Refer to the documentation on a particular protocol (FC, iSCSI or SRP) for details.

Target and Initiator Groups

Target and initiator groups define sets of targets and initiators that can be associated with LUNs. A LUN that is associated with a target group can only be seen via the targets in the group. If a LUN is not explicitly associated with a target group, it is in the default target group and will be accessible via all targets, regardless of protocol. Similarly, a LUN can only be seen by the initiators in the group or groups to which it belongs. If a LUN is not explicitly associated with an initiator group, it is in the default initiator group and can be accessed by all initiators. While using the default initiator group can be useful for evaluation purposes, its use is discouraged since it may result in exposure of the LUN to unwanted or conflicting initiators.

To avoid possible LUN conflicts when an initiator belongs to multiple groups, configure initiators within all groups before associating groups with LUNs.

BUI

To configure targets, go to the Configuration > SAN page, use Fibre Channel, iSCSI, and SRP to navigate, and then configure the Ports, Initiator, and Target Groups controls.

To associate a LUN, go to the Shares > Shares > Protocols page and then configure the Target Group and Initiator Group controls.

CLI

Use the configuration san context of the CLI to operate on targets and initiators by protocol type. Then, use the shares CLI context to create LUNs and associate them with target and initiator groups.

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	Oracle ZFS Storage Appliance Administration Guide