HP ProLiant DL100 G2 DPSS, Administration Manual

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Primary storage
Secondary storage
Tertiary storage
Fibre Channel and SCSI disk storage
Serial ATA disk storage
Tape
Storage
Optical
archive
gl0057
Figure 1 Tiered storage
iSCSI technology
The iSCSI protocol de fi nes the rules and processes for transporting SCSI (block-level) data over a TCP/IP
network. The iSCSI standard follows the SCSI architectural model, which is based on message exchange
between an initiator and a target. In the SCSI model, initiators and targets are identi fi ed by a unique
SCSI device name. Because iSCSI transport occurs over a network fabric instead of a direct cable
connection, the initiator and target have multiple IP addresses associated with their iSCSI names.
The following is an example of what occurs during a message exchange between an initiator and
a target. The process begins when an application sends a request to the operating system (OS) to
read or write data. The OS generates the appropriate SCSI commands and data request in the form
of a message. Before the message can be sent over an IP network, it is processed through iSCSI to
encapsulate the request into the TCP/IP protocol stack (attaching routing, error checking, and control
information) for transmission over the network. This can be accomplished using driver- or OS-level
software, or it can be of fl oaded to the host bus adapter (HBA). The HBA transmits the packets over the IP
network. When the packets reach the target device, they go through a reverse process to reassemble
(sequence) the data, which is then moved to the SCSI controller. The SCSI controller ful fi lls the request by
writing data to, or reading data from, the target device. If it is a read transaction, the target returns data
to the initiator using the iSCSI protocol.
For further information about HP StorageWorks iSCSI products, visit
http://www.hp.com/go/nas .
Windows Storage Server 2003 editions
Windows Storage Server 2003 is a dedicated fi le and print server application based on Windows Server
2003, with dependability and seamless integration in networked storage. Windows Storage Server
2003 integrates with existing infrastructures and supports heterogeneous fi le serving as well as backup
and replication of stored data. Windows Storage Server is also an ideal solution for consolidating
multiple fi le servers into a single solution that enables cost reduction and policy-based management of
storage resources. Windows Storage Server 2003 includes advanced availability features such as
point-in-time data copies, replication, and server clustering. Because Windows Storage Server 2003
solutions are precon fi gured, they can be deployed out of the box in a short time, and the HP Storage
Server Management Console makes management easy. Windows Storage Server 2003 integrates with
existing infrastructures, so enterprises can make full use of commonly-used network environments and
HP ProLiant DL100 G2 Storage Server administration guide
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