Intel RAID Controllers Alert Code Decoding White Paper

Intel® RAID Controllers: SAS Software Stack Appendix A

Revision 1.0

Sense Code Qualifier. These bytes can be decoded into an error message for more

information.

5. The logged entry also includes the following:

- Date and time of the event

- Channel and target

- SAS/SATA CDB

- Returned Sense Code

6. Returned Sense Data includes:

- Sense Key = byte 2

- Additional Sense code = byte 12

- Additional Sense Code Qualifier = byte 13

1.4 Unexpected Sense Code Event Format

The error message format may vary depending on the utility used to view or extract the

message. The general format is shown below.

Date – Controller ID - Error type - Device Number - CDB in Hex - Sense in Hex.

Below is an example of a sense code based error message from an Intel

SAS RAID controller.

[Warning, 1] 2007-09-07, 09:57:17 Controller ID:0 Unexpected sense:PD=2:10,

CDB = 0x2a 0x00 0x00 0x02 0xf2 0x00 0x00 0x00 0x80 0x00, Sense = 0xf0

0x00 0x0b 0x00 0x02 0xf2 0x2d 0x0a 0x00 0x00 0x00 0x00 0x4b 0x05

0x00 0x00 0x00 0x00

CDB and Sense Code data is in hex. Each byte is represented by data in a “0x00” format,

separated by a space and numbered on the left starting at 0. The CDB bytes above would be

numbered as follows.

Byte Byte Byte Byte Byte Byte Byte Byte Byte Byte

0 1 2 3 4 5 6 7 8 9

0x2a

0x00 0x00 0x02 0xf2 0x00 0x00 0x00 0x80 0x00

Tables in this document will not include the 0x portion of the byte.

1.5 SCSI CDB Command Decode

The SCSI CDB commands are defined as the data structure viewed through the SCSI interface.

A single command will transfer one or more logical blocks of data. The CDB consists of the

operation code, the logical unit number, the command parameters and the control byte. The

length varies depending on the value of the group code in the operation code. Intel

RAID

controllers addressed in this document support 4 kinds of the CDB length – 6-byte commands,

10-byte commands, 12-byte commands and 16-byte commands.

The table below describes the general content of the 6-byte CDB. The current SAS

implementation of the CDB can be of variable length with some reserved portions indicating a

target block on the target device. The table below is limited to 6 bytes and is used to highlight

the Operational Code byte.