Maxtor 10K III manual QFG04h, Pre0COG-empt

SCSI Description

%QFG04h

Pre0COG-empt

A PERSISTENT RESERVATION OUT&GUETKRVKQPcommand with a successful Pre-empt ser- vice action removes all persistent reservations for all initiators that have been registered with the Service action Reservation key specified in the PERSISTENT RESERVATION OUT command’s parameter list. A persistent reservation is also established for the pre-empting initiator. Any commands from any initiator that have been accepted by the device server as non-conflicting continue their nor- mal executions. If a PERSISTENT RESE VATION OUT command is sent that specifies a Pre-empt service action and no persistent reservation exists for the initiator identified by the Service action eservation key, it is not an error con- dition.

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 RES- ERVATIONS PREEMPTED. Commands that follow are subject to the persistent reservation restrictions set by the pre-empting initiator.

The persistent reservation thus created by the pre-empting initiator is defined by the Scope and Type fields of the PERSISTENT RESERVATION OUT com- mand and the corresponding fields of the command’s parameter list.

The registration keys for the pre-empted initiators are removed by the Pre-empt service action; 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 ac- tions and reservation actions are performed.

Note that persistent reservations are not superseded by a new persistent res- ervation from any initiator except by the execution of a PERSISTENT RESER- VATION OUT that specifies either the Pre-empt or the Pre-empt and Clear service actions. New persistent reservations that do not conflict with an exist- ing persistent reservation execute normally. The persistent reservation of a log- ical unit or extents having the same Type value are permitted if no conflicting persistent reservations other than the reservations being pre-empted are held by another initiator.

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

5-100 Maxtor Atlas 10K III