17 persistent reserve out command, Persistent reserve out command – Seagate Fibre Channel Interface User Manual
Page 268
254
Fibre Channel Interface Manual, Rev. D
12.17
Persistent Reserve Out command
The Persistent Reserve Out command is used to request service actions that reserve a logical unit or element
for the exclusive or shared use of a particular initiator. This command is used in conjunction with the Persistent
Reserve In command and should not be used with the Reserve and Release commands.
Initiators performing Persistent Reserve Out service actions are identified by a reservation key provided by the
application client. An application client may use the Persistent Reserve In command to identify which initiators
are holding a persistent reservation and use the Persistent Reserve Out command to preempt that reservation
if required.
If a Persistent Reserve out command is attempted, but there are insufficient device server resources to com-
plete the operation, the device server returns a Check Condition status. The sense key is set to Illegal Request
and the additional sense data is set to Insufficient Registration Resources.
The Persistent Reserve Out command contains fields that specify a persistent reservation service action, the
intended scope of the persistent reservation, and the restrictions caused by the persistent reservation. If a
Scope field specifies a scope that is not implemented, the device server returns a Check Condition status. The
sense key is set to Illegal Request and the additional sense data is set to Invalid Field in CDB.
Fields in the Persistent Reserve out parameter list specify the information required to perform a particular per-
sistent reservation service action.
Field definitions (listed alphabetically)
Control
See Control Byte in Section 11.2.1.6.
Parameter List Length
24 (18h)
If the parameter list length is set to something other than 24, the device server returns a Check Condition
status, the sense key is set to Illegal Request, and the additional sense data is set to Parameter List Length
Error.
Scope
See definition on page 252. If the Scope field specifies a scope that is not implemented, the device server returns a Check
Condition status, the sense key is set to Illegal Request, and additional sense data is set to Invalid Field in CDB.
Table 166: Persistent Reserve Out command (5Fh)
Bit
Byte
7
6
5
4
3
2
1
0
0
0
1
0
1
1
1
1
1
1
Reserved
Service Action
2
Scope
Type
3
Reserved
4
Reserved
5
Reserved
6
Reserved
7
(MSB)
Parameter List Length (18h)
8
(LSB)
9
Control
5Fh
Table
number