Hitachi HUS154530VLF400 User Manual
Hitachi Ultrastar 15K450 (FC-AL) Hard Disk Drive Specification
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17.0 FC-AL attachment
This section defines some basic terminology and describes the behavior of the drive when attached to a Fibre Channel Arbi-
trated Loop.
trated Loop.
17.1 Fundamentals
This section introduces some of the terminology that is used in describing Fibre Channel and FC-AL.
Fibre Channel is logically a bi-directional serial data channel between two Nodes. Nodes are physically connected by a Link;
the point of connection between the link and the node is called a Port.
the point of connection between the link and the node is called a Port.
Ports may be connected point-to-point by a single link or by a switching network (Fabric). If the port is part of the Fabric it is
called an F_Port, otherwise it is an N_Port.
called an F_Port, otherwise it is an N_Port.
Fibre Channel is defined in terms of a hierarchy of functions or 'protocol layers'.
•
FC-0: Physical Link
•
FC-1: Transmission Protocol
•
FC-2: Signaling and Framing Protocol
•
FC-3: Common Services
•
FC-4: Mapping
All layers except FC-4 are defined in
•
“Fibre Channel Physical and Signaling Interface (FC-PH)” - ANSI
The Arbitrated Loop is an extension of FC-1 and FC-2 that allows more than two nodes to be connected without the expense of
a Fabric. A port that connects to an Arbitrated Loop is generally referred to as an L_Port. However, the terms NL_Port and
FL_Port are also used if it is necessary to distinguish whether or not the L_Port is part of a Fabric. FC-AL is defined in:
a Fabric. A port that connects to an Arbitrated Loop is generally referred to as an L_Port. However, the terms NL_Port and
FL_Port are also used if it is necessary to distinguish whether or not the L_Port is part of a Fabric. FC-AL is defined in:
•
“Fibre Channel Arbitrated Loop (FC-AL)” -ANSI
FC-4, the Mapping layer, defines how other communication protocols (e.g. SCSI, IPI-3, HIPPI) may use Fibre Channel func-
tions. The FC-4 used by The Drive is SCSI-FCP, which is defined in:
tions. The FC-4 used by The Drive is SCSI-FCP, which is defined in:
•
“Fibre Channel Protocol for SCSI (SCSI-FCP)” -ANSI
The 'Disk Profile', recommends which features from the other documents should and should not be implemented in order to
ensure compatibility between devices from different manufacturers. The full title of the Disk Profile is:
ensure compatibility between devices from different manufacturers. The full title of the Disk Profile is:
•
“Fibre Channel Private Loop SCSI Direct Attach (FC-PLDA)” -ANSI
An additional document, the ‘Public Loop Profile’, describes the additional features needed to support communication over a
FC Fabric Topology. In addition to communicating with devices on their local loop, Public Loop devices can also communi-
cate to devices across a network through the use of a “Fabric Port.” Public Loop behavior is defined in:
FC Fabric Topology. In addition to communicating with devices on their local loop, Public Loop devices can also communi-
cate to devices across a network through the use of a “Fabric Port.” Public Loop behavior is defined in:
•
“Fibre Channel - Fabric Loop Attach (FC-FLA)” -ANSI
The Drive complies with the FC-FLA, which makes the following requirements:
1. The upper two bytes of the device’s NL_Port ID must not be zero.
2. The device must be able to communicate with the Fabric Port i.e., open AL_PA 0x00.
2. The device must be able to communicate with the Fabric Port i.e., open AL_PA 0x00.