4.1 Control/Sense Commands

Persistent reservations scope

The value in the "Scope" field shall indicate whether a persistent reservation applies to an entire logical unit or to an element. The values in the "Scope" field are defined in Table 4.28.

Table 4.28 Persistent reservations scope

Code

Name

Description

 

 

 

0h

Logical Unit

Persistent reservation applies to the full logical unit

1h

Reserved

Reserved

2h

Element

Persistent reservation applies to the specified element

 

(not supported)

 

3h-Fh

Reserved

Reserved

 

 

 

a)Logical unit scope

A "Scope" field value of LU shall indicate that the persistent reservation applies to the entire logical unit. A drive that supports PERSISTENT RESERVE OUT must also support the Logical Unit scope.

b)Element scope (not supported)

This "Scope" field value indicates that reservation has been applied to the element specified in the "Scope-specific Address" field of the PERSISTENT RESERVE OUT parameter list. The support of Element Scope is optional.

Persistent reservations type

The "Type" field value defines the reserve attribute applied to the data block in the logical unit. Table 4.29 shows the characteristics of each of the type codes. The codes for each of the types and the drives that support such codes are explained in the table. The requirements of the drives indicated in the table are divided into two separate categories. The first paragnaph defines the required handling for read operation. The second paragraph defines the required handling for write operations.

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Fujitsu MBA3147RC, MBC2036RC, MBC2073RC, MBA3300RC, MBA3073RC ∙ Persistent reservations scope, ∙ Persistent reservations type