Hitachi Ultrastar 15K450 (FC-AL) Hard Disk Drive Specification
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Note: Common FC Services are used to communicate with the Fabric Name Server and are only issued by the drive when it is
operating as a Public Loop Device.
Table 81:Payload of a CT Header
The FC_CT field contains the FC_CT revision. The drive always sets this value to 0x01.
IN_ID is a reserved field that may be used to carry the S_ID of the original requestor between different servers in the fabric.
Its value in the FC_ACC/FC_FJT frame may be non zero if it was used.
The FCS_Type indicates which FC Service is requested and the FCS_Subtype specifies which server will process the
request. The drive does not check the FCS_Type/FCS_Subtype values returned by the Name Server in the FS_ACC/FS_RJT.
The Options field specifies various options used during FCS processing. The drive sends a value of 0x00, which specifies that
this request must complete before another can be attempted.
The Command/Response Code field identifies specific Fibre Channel Service Information Units (FS_IUs). The Command/
Response Code also determines the type of FS_IU. Command codes are as shown in Table82.
Table 82:Command/Response Codes
The drive supports only the Command code of 0217h, which specifies a RFT_ID request.
The Maximum/Residual Size field is used by the sender of an FS_REQ to indicate the maximum number of bytes it can
accept in an FS_ACC payload. If the size of the responder’s FS_ACC payload is greater than this value, the responder will
Byte Item Size (Bytes)
0 FC_CT 1
1-3 IN_ID 3
4FCS_Type 1
5 FCS_Subtype 1
6Options 1
7Reserved 1
8-9 Command/Response Code 2
10-11 Maximum/Residual Size 2
12 Reserved 1
13 Reason Code 1
14 Reason Code Explanation 1
15 Vendor Unique 1
Value Description
0000h Non-(FS_IU)
0001h - 7FFFh Fibre Channel Service Requests (FS_REQ)
8001h Fibre Channel Service Reject (FS_RJT)
8002h Fibre Channel Service Accept (FS_ACC)
other values Reserved