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Table
Data Field | Description |
Service Action | Service actions that require information about persistent reservation and registrations may require |
| enabling of nonvolatile memory within the logical unit. |
| Service action codes available are: |
| Code Name Description |
| 00h Read Keys Reads all registered Reservation keys |
| 01h Read Reservations Reads all current persistent reservations |
| 02 – 1Fh Reserved |
| A “Read Keys” service action requests that the device server return a parameter list that includes |
| a header and a complete list of all of the reservation keys currently registered with the device serv- |
| er. If multiple initiators have registered with the same key, then the key is listed multiple times, |
| once for each registration. Refer to Table |
| parameter data. |
| A “Read Reservation” service action requests that the device server return a parameter list that |
| contains a header and a complete list of all persistent reservations that are presently active in the |
| device server and its extents. Note that duplicate persistent reservations from the same initiator are |
| not reported. Refer to Table |
| rameter data. |
Allocation | This field indicates how much space has been reserved for the returned parameter list (Read Keys |
Length | or Read Reservations parameters). The actual length of the parameter data is indicated in the pa- |
| rameter data field for those parameters. |
| If the Allocation Length is not sufficient to contain the entire list of parameters, the first portion |
| of the list that does fit is returned. If it is determined that the remainder of the list is required, the |
| client should send a new PERSISTENT RESERVATION IN command with an Allocation Length |
| field large enough to contain the entire list of parameters. |
The data format and field descriptions for the Read Keys Parameters are described in Table
Table
Bit | 7 | 6 | 5 |
| 4 |
| 3 |
| 2 | 1 | 0 |
Byte |
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0 - 3 | (MSB) |
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| Generation |
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4 - 7 | (MSB) |
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| Additional Length (n – 7) |
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| (Reservation Key List Follows in Bytes 8 – n) |
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8 - 15 | (MSB) |
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| First Reservation Key |
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n – 7 to n | (MSB) |
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| Last Reservation Key |
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