Code

Name

Description

 

 

A PERSISTENT RESERVATION OUT command with a successful Pre-empt service ac-

 

 

tion removes all persistent reservations for all initiators that have been registered with the

 

 

Service action Reservation key specified in the PERSISTENT RESERVATION OUT com-

 

 

mand’s parameter list. A persistent reservation is also established for the pre-empting initi-

 

 

ator. Any commands from any initiator that have been accepted by the device server as non-

 

 

conflicting continue their normal executions. If a PERSISTENT RESERVATION OUT

 

 

command is sent that specifies a Pre-empt service action and no persistent reservation exists

 

 

for the initiator identified by the Service action Reservation key, it is not an error condition.

 

 

A UNIT ATTENTION condition is established for the pre-empted initiators. The sense key

 

 

is set to UNIT ATTENTION; the additional sense data is set to RESERVATIONS PRE-

 

 

EMPTED. Commands that follow are subject to the persistent reservation restrictions set by

 

 

the pre-empting initiator.

04h

Pre-empt

The persistent reservation thus created by the pre-empting initiator is defined by the Scope

and Type fields of the PERSISTENT RESERVATION OUT command and the correspond-

 

 

ing fields of the command’s parameter list.

 

 

The registration keys for the pre-empted initiators are removed by the Pre-empt service ac-

 

 

tion; the reservation key for an initiator that has performed a Pre-empt service action with

 

 

its own Reservation key specified in the Service action Reservation key remains unchanged,

 

 

although all other specified releasing actions and reservation actions are performed.

 

 

Note that persistent reservations are not superseded by a new persistent reservation from any

 

 

initiator except by the execution of a PERSISTENT RESERVATION OUT that specifies

 

 

either the Pre-empt or the Pre-empt and Clear service actions. New persistent reservations

 

 

that do not conflict with an existing persistent reservation execute normally. The persistent

 

 

reservation of a logical unit or extents having the same Type value are permitted if no con-

 

 

flicting persistent reservations other than the reservations being pre-empted are held by an-

 

 

other initiator.

 

 

Note: Service Action (Code) 4 is not supported by Atlas 10K V.

Maxtor Atlas 10K V

5-85