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Bus release deferred errors, Sense keys – HP Q153090901 User Manual

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REQUEST SENSE 03h

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reported. When the host reads sense data with a

REQUEST SENSE

, it will see an error for the

WRITE

with residue information indicating data lost for that write and previous writes.

If the command is not a write command and the Deferred Error check is performed as part

of the pre-execution checks,

CHECK CONDITION

status is reported. The

DEFERRED ERROR

sense is copied to Current sense. The

DEFERRED ERROR

sense is cleared. The host is

expected to retrieve the sense by sending a

REQUEST SENSE

, otherwise the data will be lost.

Bus release deferred errors:

The drive will release the bus to terminate an operation (such as

READ

) when the host sends an

ABORT

message or when the drive fails to send status due to a catastrophic error.

In each case, the operation does not terminate immediately since the logical position will have to

be established on the other side of the block that was about to be transferred, or was being

transferred. If an error subsequently occurs while trying to complete the read, the sense generated

is a

DEFERRED ERROR

. It is therefore possible but highly unlikely to have

DEFERRED ERROR

sense

flagged for a command without immediate report.

Sense keys

The following table lists the sense keys that may be returned by HP Ultrium drives. SCSI sense keys

are 4-bit codes returned in the sense data. They indicate in what general area the problem that

has just been experienced falls. For a clearer indication of the nature of the problem, refer to the

additional sense code.

Code Name

Description

ASC/Qs

0h NO SENSE

There is no real problem. The sense information is

probably indicating some condition (such as

encountering a filemark).

0000h, 0001h, 0002h,

8282h

1h RECOVERED ERROR Returned if a Mode Select parameter is truncated

or if a TapeAlert event is being reported.

5D00h, 3700h

2h NOT READY

The drive is not in a state to be able to execute

the request. See also the Media Access check.

0400h, 0401h, 0402h,

3003h, 3007h, 3A00h,

3E00h

3h MEDIUM ERROR

The command failed, believed to be caused by a

problem with the tape.

0002h, 0004h, 0407h,

0410h, 0C00h, 1100h,

1102h, 1400h, 3001h,

3002h, 3004h, 3100h,

3B00h, 5000h, 5200h,

5300h

4h HARDWARE ERROR The command failed, believed to be caused by a

problem with the drive hardware.The FRU in the

sense data should indicate which part of the

hardware is faulty.

0403h, 40XXh, 4400h,

5100h, 5300h