HP StorageWorks 4000/6000/8000 - Enterprise Virtual Arrays, Справочное руководство

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• iSCSI initiator (IP host)—A system that starts the exchange of information with an iSCSI target. IP
hosts access the iSCSI target storage systems as if they were directly attached.
iSCSI naming
iSCSI nodes are uniquely named devices (initiators or targets). The nodes have an IP address, TCP
port, and iSCSI name. The iSCSI name can be up to 255 characters in length.
Figure 126 shows an
iSCSI node definition in the context of an IP network.
25161a
IP Network = Network Entity
iSCSI Node (IP device with IP address)
iSCSI Name (up to 255 characters, using either EQN or EUI naming scheme)
Network Portal (IP address and TCP port number)
iSCSI Device (host or storage device)
iSCSI Node
iSCSI Node
Figure 126 iSCSI node definition
.
The iSCSI name is independent of the network portal and provides a unique and consistent identity
for an iSCSI node. Although moving a device to another network segment changes its network portal,
the iSCSI name is unchanged and allows the device to be rediscovered.
An iSCSI name is independent of supporting hardware. You can assign an iSCSI name to a device
driver on a host, even if the device driver accesses the network through multiple NICs. A storage
device with multiple connections to the network is also identified by its iSCSI name.
iSCSI naming provides permanent and unique identities for iSCSI nodes. The two naming schemes
are as follows:
• IQN
• EUI
An iSCSI node address consists of the IP address, TCP port number, and IQN or EUI. iSCSI nodes
acquire IP addresses with standard IP services.
Discovery mechanisms
This section describes the mechanisms you can use for discovery requests.
Static configuration
With static configuration, an administrator manually sets the target addresses for the initiators. The
statically configured addresses for the targets persist across initiator reboots. Static configuration is
recommended for the smallest iSCSI SANs.
SAN Design Reference Guide 357