Dell™ PowerVault™ ML6000 SCSI Reference Guide www.dell.com | support.dell.
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Contents 1 SCSI Command Support 1 Device Model. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Controller Device Commands and Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Media Changer Commands and Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 General Command Support Behavior . . . . . . . . . . . . . .
Log Sense - 4Dh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . What the Library Does with This Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Command Usage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Log Sense CDB Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Read Buffer – 3Ch. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . What the Library Does With This Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Command Usage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Read Buffer CDB Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Tables Table 1 Controller Device Supported Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Table 2 Controller Device Supported Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Table 3 Media Changer Supported Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Table 4 Media Changer Device Supported Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 25 Tape Alert Log Page Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Table 26 MODE SELECT CDB format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Table 27 Mode Parameter Header format for Mode Select (6) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Table 28 MODE SELECT CDB format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 56 Echo Buffer Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 Table 57 READ ELEMENT STATUS CDB format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 Table 58 Element Type Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 Table 59 Element Status Header format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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SCSI Command Support Device Model The Dell™ PowerVault™ ML6000 tape library supports both a Media Changer device (device type 08h) and a Controller device (device type 0Ch). This approach is used primarily to aid initialization and discovery for the servers in conjunction with the library’s Logical Library model.
Controller Device Commands and Parameters The following table lists the commands supported by the Controller device. For the PowerVault ML6000, these commands apply only when a DA blade is present in the library.
Media Changer Commands and Parameters The following table lists the commands supported by the Media Changer device.
The following table lists the parameters supported by the Media Changer device. The Media Changer does not support any diagnostic parameters.
General Command Support Behavior Multiple Initiator Support Multiple initiators are not supported on the SCSI interface. Information such as unit attentions and sense data will be held for only a single initiator. Multiple initiators are supported on the Fibre Channel interface. Unit attentions and sense data will be held for each initiator. Element Addressing The element-addressing model follows that of previous Dell libraries.
For a complete list of all possible sense data and their causes, refer to Request Sense – 03h on page 70. This status information will not be separated by individual commands. Status values of Condition Met, Intermediate Condition Met, and Queue Full are not currently used. The Initiator should issue a Request Sense command to determine the precise cause of the Check Condition status and clear it.
Reserved Fields Reserved fields are not checked, and no error will be sent if they contain non-zero values. Online/Offline Operation Each Media Changer device can be placed in either an online or offline mode. The purpose of these modes is to configure whether the Media Changer is being controlled by a SCSI initiator or by the operator panel. When the Media Changer is online, a SCSI initiator is controlling it and all SCSI commands are supported.
Table 6 Supported SCSI Messages (Continued) Message Code Direction Description RESTORE POINTERS 03h In This message is sent from the target to direct the initiator to continue sending data. DISCONNECT 04h In This message is sent by the target to inform an initiator that the present data transfer will be suspended. The target will reselect the initiator at a later time to continue the current operation.
Logical Libraries The underlying physical library is not exposed externally to applications. Rather, logical representations of one to 18 Media Changer devices are created, and these are presented instead. Through this method the physical library can be partitioned and concurrently shared in a heterogeneous environment. Storage and Data Transfer elements cannot be shared across logical libraries; they can only be assigned to one logical library at a time.
Element status for the Data Transfer element being cleaned will not reflect the presence of the cleaning cartridge. It will continue to report that it is empty and accessible. Removed Drives Depending on how the library is configured, occasionally Data Transfer elements will be reported where no drive is physically present at the time. This could be due to a drive that has been removed for service, or simply a placeholder for the addition of a future drive.
SCSI Commands Initialize Element Status - 07h What the Library Does With This Command The library will determine status (full or empty) for all elements, as well as barcode label information (volume tags) for the media. Barcode labels will be scanned unless otherwise directed (and the library supports a non-barcode option). The library may not fully execute this command if the Automatic Inventory option is enabled, and element status is already known.
Initialize Element Status CDB Format The INITIALIZE ELEMENT STATUS CDB format is shown in the following table. Table 7 INITIALIZE ELEMENT STATUS CDB format Bit Byte 7 6 0 1 5 4 3 1 0 Op Code (07h) Logical Unit Number Reserved 2 Reserved 3 Reserved 4 Reserved 5 2 NBL Control No Barcode Labels (NBL) – A value of 0 indicates that the specified elements will be checked for all relevant status, including bar code labels.
Initialize Element Status With Range - E7h What the Library Does With This Command The library will examine the range of elements requested and determine their status relative to media presence (full or empty). Barcode labels will be scanned unless otherwise directed (and the library supports a non-barcode option). The library will always fully execute this command regardless of the Automatic Inventory setting.
Number of Elements - This field specifies the number of elements to check. Gaps in element types and addresses are automatically handled until a quantity of physical elements equal to this number has been checked. If this field is 0, the range checked will start with the Starting Element Address and continue through all remaining elements. This field is ignored if the Range field is 0.
Inquiry - 12h What the Library Does With This Command In response to this command the library returns static data that describes various subsystem parameters. Each Controller and Media Changer logical unit will return its own Inquiry data. If an INQUIRY command is received from an initiator with a pending unit attention condition, the library will perform the INQUIRY command and will not clear the unit attention condition.
Standard Inquiry Response Table 10 Bit Byte 0 1 Standard Inquiry Response 7 6 5 4 Peripheral Qualifier 2 1 0 Peripheral Device Type RMB Reserved 2 3 3 Version AERC Obsolete NormACA 4 HiSup Response Data Format Additional Length 5 SCCS Reserved 6 BQue EncServ BarC MultiP MChngr Obsolete Obsolete Addr16 7 RelAdr Obsolete Wbus16 Sync Linked Obsolete CmdQue SftRe 8 Vendor Identification 15 16 Product Identification 31 32 Firmware Revision Level 35 36 Full Firmware Revis
Additional Length – For the Media Changer logical units, this field returns 33h, indicating 51 additional bytes of data are available. For the Controller logical unit, this field returns 1Fh, indicating 31 additional bytes of data (following this field) are available to the initiator. SCC Supported (SCCS) – For the Media Changer logical units, this field returns a 0. For the Controller logical unit, this field returns a 1. Basic Queuing (BQue) – Returned as 0, indicating basic queuing is not supported.
Supported Vital Product Data Page (00h) Table 11 Supported Vital Product Data Page (00h) Bit Byte 0 7 6 5 4 Peripheral Qualifier 3 2 1 0 Peripheral Device Type 1 Page Code (00h) 2 Reserved 3 Page Length 4 First Page Code Supported 5 Second Page Code Supported 6 Third Page Code Supported Peripheral Qualifier - The return value 000b indicates that the library supports the peripheral device type at the specified LUN.
Unit Serial Number Page (80h) Table 12 Unit Serial Number Page (80h) Bit Byte 0 7 6 5 Peripheral Qualifier 4 3 2 1 0 Peripheral Device Type 1 Page Code (80h) 2 Reserved 3 Page Length 4 Serial Number 27 Peripheral Qualifier – The return value 000b indicates that the library supports the peripheral device type at the specified LUN. This field returns 011b if no peripheral device types are supported at that LUN.
Device Identification Page (83h) Table 13 Device Identification Page (83h) Bit Byte 7 0 6 5 4 3 Peripheral Qualifier 2 1 0 Peripheral Device Type 1 Page Code (83h) 2 Reserved 3 Page Length (n-3) Identification Descriptors 4 First Identification Descriptor ... ... ... ... Last Identification Descriptor N Peripheral Qualifier – The return value 000b indicates that the library supports the peripheral device type at the specified LUN.
Association – This field returns the following values: • 0h – the Identifier field is associated with the address physical or logical device • 1h – the Identifier field is associated with the port that received the request Identifier Type – This field returns the following values: • 1h – The identifier is a concatenation of the Vendor Identification field from the Standard Inquiry response and the Serial Number field (without the Vendor Identification prefix) from the Unit Serial Number page.
The first two descriptors describe the Node and Port.
The eight-byte Node and Port Worldwide Names have the following format: Table 18 Node and Port Worldwide Names MSB LSB Table 19 4-bit NAA ID 24-bit Company ID 36-bit Vendor Specified Identifier 5h 00 30 8C Assigned per library Controller Port Number Identification Descriptor Bit Byte 7 6 0 1 5 4 3 Reserved Reserved Association = 1h Reserved 3 Identifier Length = 04h 4 Port Number (Starting with 1) PowerVault ML6000 SCSI Reference Guide 1 0 Code Set = 1h 2 7 2 Identifier Type=
Log Sense - 4Dh What the Library Does with This Command The library returns information for the requested log page. The only supported log page is the Tape Alert page, with a limited set of flags. The library will return the current values of the flags on request, and then clear them. Command Usage This command can be used to monitor conditions of the library. Log Sense CDB Format The LOG SENSE CDB format is shown in the following table.
Page Code – The Page Code field identifies which log page is being requested by the initiator. Table 21 Page Code Page Code field Page Name Page Description 00h Supported Log Pages Returns list of supported log pages 2Eh Tape Alert Log Returns the 64 tape alert flags Parameter Pointer - This field specifies which log parameter to begin with for the requested log page.
Log Parameters – These are dependent upon the log page. The various parameters as well as their format for the supported pages are listed below. Table 23 Bit Byte Log Parameter Format 7 6 5 4 3 2 1 0 LBIN LP 0 Parameter Code 1 2 3 DU DS TSD ETC TMC Parameter Length (n-3) 4 Parameter Value n Parameter Code – This field identifies which log parameter was transferred. The valid values for this field depend on the log page. Disable Update (DU) – Will be set to 0.
Supported Log Page (00h) This page returns a list of all log pages supported by the library. Table 24 Bit Byte Supported Log Page (00h) 7 0 6 5 4 Reserved 3 2 1 0 Page Code (000000b) 1 Reserved 2 Page Length (0002h) 3 4 Supported Log Page (00h) 5 Tape Alert Log Page (2Eh) Page Code – The returned value is 00h, indicating this page. Page Length – The returned value is 0002h. The page codes for all the supported pages (including this one) follow the page length field.
The supported Tape Alert flags are: Flag 1: Drive Communication Failure (C) - This flag is set to indicate a drive communication failure. Flag 2: Library Hardware B (W) - This flag is set for any unrecoverable mechanical error. Flag 4: Library Hardware D (C) - This flag is set when the internal Power-On-Self-Tests (POST) fail or when a mechanical error occurs that requires a power cycle to recover, and is not internally cleared until the device is powered off.
Mode Select (6) - 15h What the Library Does With This Command The library does not support any changeable parameters, and this command is supported for compatibility only. This command can be issued to both the Controller logical unit as well as a Media Changer logical unit. The mode pages supported by each device vary however.
Mode Parameter Header Following the MODE SELECT CDB, a single Mode Parameter Header should be sent as shown in the following table. For both the controller and Media Changer devices, none of the fields are actually used however, and should all be set to zero.
Mode Select (10) - 55h What the Library Does With This Command The library does not support any changeable parameters, and this command is supported for compatibility only. This command can only be issued to the Controller logical unit. Libraries without DA blades do not support this command.
Mode Parameter Header Following the MODE SELECT CDB, a single Mode Parameter Header should be sent as shown in the following table. For the controller device, none of the fields are actually used however, and should all be set to zero.
Mode Sense (6) - 1Ah What the Library Does With This Command The library will return the current settings for the supported mode pages. This command can be issued to the Controller logical unit as well as the Media Changer logical units. The mode pages supported by each device vary. Command Usage This command can be used to determine certain operational settings governing the behavior of the library.
Page Control (PC) - This field indicates the type of mode page parameter values to return as shown in the following table Table 31 Page Control (PC) field Page Control 0 0 Description Report current values defined by: • The values set by the last successful MODE SELECT command. • The default values if no saved values exist.
Mode Sense (10) - 5Ah What the Library Does With This Command The library will return the current settings for the supported mode pages. This command can only be issued to the Controller logical unit. Command Usage This command can be used to determine certain operational settings governing the behavior of the library. Use of MODE SENSE to obtain these parameters during initialization is highly recommended to facilitate the most flexibility in supporting the library.
Page Control (PC) - This field indicates the type of mode page parameter values to return as shown in the following table. Table 34 Page Control (PC) field Page Control Description 0 Report current values defined by: 0 • The values set by the last successful MODE SELECT command. • The default values if no saved values exist.
Mode Pages The following table lists the mode pages supported by the library. Table 36 Page Code Supported Mode Pages Page Name Page Description Device 02h Disconnect Reconnect Provides information regarding the physical bus performance characteristics. Controller 18h Fibre Channel Logical Unit Control Provides Fibre Channel control information that is associated with the logical unit.
Disconnect-Reconnect Page (02h) The Disconnect-Reconnect mode page is only supported by the Controller logical unit, and describes the interconnect tenancy characteristics of the Fibre Channel interface. An interconnect tenancy is a period of time during which a SCSI device owns or may access the interface. This page is not available on the SCSI interface.
Connect Time Limit – This field indicates the maximum duration of an interconnect tenancy. A value of 0 is returned to indicate that there is no connect time limit. Maximum Burst Size – This field indicates the maximum amount of data that will be transferred during a single data transfer operation. The value is expressed in increments of 512 bytes. A value of 4 is returned, indicating a maximum burst size of 2048 bytes.
Fibre Channel Port Control Page (19h) The Fibre Channel Port Control mode page reports port behavior for the Fibre Channel Protocol. This mode page is not available on the SCSI interface. This mode page is only supported by devices at LUN 0.
address. If the hard address has not changed from the address obtained in a previous successful loop initialization, the target will attempt to obtain the address in the LIFA phase if a valid Fabric Login exists or LIPA phase of loop initialization. If the hard address has changed, the target will attempt to obtain the new address in the LIHA phase.
Log Errors (LogErr) – This field is set to 0 to indicate that logging of informational exception conditions is vendor specific (unique to the library in this case). Test – This field is set to 0 to indicate that test failure indications will not be generated. Disable Exception Control (Dexcpt) –This field is set to 1, indicating that the initiator must poll the LOG SENSE Tape Alert page. Enable Warning (EWasc) – This field is set to 0, indicating that reporting of warnings is disabled.
Element Address Assignment Page (1Dh) The Element Address Assignment mode page returns the first element address and the element quantity for each element type. The quantity is based on the number of elements configured in the library, some of which may be temporarily removed (like a storage magazine or drive). Elements that are temporarily removed will not change the overall number of elements for that element type. Table 41 shows the format of the page.
First Storage Element Address – This field returns 1000h, which is the address of the first storage element. Number of Storage Elements – This field varies, depending on the configuration of the subsystem. First Import/Export Element Address – This field returns 0010h, which is the address of the first Import/ Export element. Number of Import/Export Elements – This field varies, depending on the configuration of the subsystem. If no Import/Export elements are installed, this field returns zero.
Device Capabilities Page (1Fh) The Device Capabilities page defines the rules governing cartridge movement within the library. It describes from which element type to the next a cartridge can be moved, directly defining which element types can be used as either source or target elements. The library does not allow the medium transport element (accessor) to be a target, and only as a source on a limited basis.
Move Medium – A5h What the Library Does With This Command The library will attempt to physically move a cartridge from the requested source element to the requested destination. The library will make reasonable attempts to retry this operation within the scope of its capabilities, but if unsuccessful, will try to return the cartridge to its source element.
Move Medium CDB Format The MOVE MEDIUM CDB format is shown in the following table. Table 44 MOVE MEDIUM CDB format Bit Byte 7 6 5 0 1 4 3 2 1 0 Op Code (A5h) Logical Unit Number Reserved 2 Medium Transport Element Address 3 4 Source Element Address 5 6 Destination Element Address 7 8 Reserved 9 10 11 Reserved Invert Control Medium Transport Element Address – This field contains the address of the Medium Transport element to use for the move.
Persistent Reserve In – 5Eh What the Library Does With This Command The library returns information about persistent reservation and reservation keys that are currently active. Command Usage This command is used in conjunction with PERSISTENT RESERVE OUT to manage persistent reservations. It can be used to retrieve a list of the current reservations and the registered reservation keys.
Read Keys Response The response for a Read Keys service action is shown the following table. Table 46 Read Keys Response Bit Byte 7 6 5 4 3 2 1 0 0 Generation 3 4 Additional Length (n-7) 7 Reservation Key List 8 First Reservation Key 15 ... n-7 Last Reservation Key n Generation – This field is a 32-bit counter that is incremented every time a PERSISTENT RESERVE OUT command requests a Register, a Register and Ignore Existing Key, a Clear, a Preempt, or a Preempt and Abort service action.
Read Reservations Response The response for a Read Reservations service action is shown in the following table.
Persistent Reserve Out – 5Fh What the Library Does With This Command The library will perform service actions relative to persistent reservations as requested. This includes creating and clearing reservations. Command Usage This command is used in conjunction with PERSISTENT RESERVE IN to manage persistent reservations. It can be used to request exclusive access to the device.
Scope – Only logical unit scope is supported, and this field must be a 0h. Type – This field specifies the type of reservation as follows: • 3h Exclusive Access – The initiator holding the persistent reservation has exclusive read and write access. Requests from any other initiators to transfer data to or from the logical unit will result in a Reservation Conflict. • 6h Exclusive Access, Registrants Only – Any currently registered initiator has exclusive data transfer access.
Position to Element – 2Bh What the Library Does With This Command The library will move the picker in front of the specified element at the current media Get position. Command Usage This command can be used to pre-position the robotics to an element to enhance performance, or it can be used as a general-purpose way to relocate the robotics without involving media movement. This might be useful for diagnostic or demonstration purposes.
Prevent Allow Medium Removal – 1Eh What the Library Does With This Command The library will prohibit movement of media to an Import/Export element when media removal has been prevented. MOVE MEDIUM commands requesting such a move will be rejected with a Check Condition indicating Medium Removal Prevented. This command does not control locking or unlocking of a mailbox. The library automatically locks mailboxes during robotic access, and unlocks them afterwards.
Read Buffer – 3Ch What the Library Does With This Command The library will return a requested buffer of data. The Controller logical unit is the primary device to use with this command, since the Media Changer logical units only support the echo buffer mode. Command Usage This command can be used primarily for enhanced domain validation. The initiator can use Descriptor mode first to determine the size of the data available to read, followed by Data mode to then read it.
In Echo Buffer Mode, data is transferred to the initiator from the echo buffer. The echo buffer will transfer the same data that was received from the last WRITE BUFFER command sent with Echo Buffer Mode. If the allocation length is insufficient to accommodate the number of bytes of data as received in the prior echo buffer mode WRITE BUFFER command, the returned data will be truncated. This is not considered an error.
Therefore the value contained in the Buffer Offset field of subsequent READ BUFFER commands should be a multiple of 2offset boundary as shown in the following table. Table 55 Offset Boundary Offset Boundary 2offset boundary Buffer Offsets 0h 20 = 1 Byte boundaries 1h 21 = 2 Even-byte boundaries 2h 22 = 4 Four-byte boundaries 3h 23 = 8 Eight-byte boundaries 4h 24 = 16 16-byte boundaries ... … FFh Not applicable Etc.
Read Element Status – B8h What the Library Does With This Command The library returns current status and information regarding the requested elements. The data is primarily derived from having done an Inventory operation (using INITIALIZE ELEMENT STATUS or INITIALIZE ELEMENT STATUS WITH RANGE), but in the case of data transfer elements is also augmented by communication with the drives.
Element Type Code – This field specifies the element types selected for the returned information, as shown in the following table. Table 58 Element Type Code Code Selected Element Type 0000b (0) All element types reported 0001b (1) Medium transport element (accessor) 0010b (2) Storage element 0011b (3) Import/Export element 0100b (4) Data transfer element (drives) Starting Element Address – This field specifies the minimum element address to report.
Read Element Status Response Element status data consists of an eight-byte header, followed by one or more element status pages (per element type). Each element status page consists of a header, followed by one or more element descriptor blocks.
Element Status Page Each element status page consists of an eight-byte header, followed by one or more element descriptor blocks. One Element Status Page header is returned for each grouping of element descriptor blocks, by element type. The format of the Element Status Page header is shown in the following table.
Primary Volume Tag Field Volume tags (returned in the Primary Volume Tag field) are basically barcode labels on the media. The library supports labels from 5 to 16 characters in length. The Primary Volume Tag field contains 32 bytes of label data (space filled to 32 bytes), followed by two reserved bytes, then two bytes of volume sequence number. The library returns zeros for the last four bytes of Primary Volume Tag data.
Additional Sense Code Qualifier – If the element is in an abnormal state, this field will be set to a value as described in Table 71 on page 72. Source Valid (Svalid) – This field is set to 1 if the Source Storage Element Address field is valid, otherwise it is set to 0. Invert – This field is set to 0. The library does not support inverting media. Source Storage Element Address – If the Source Valid field is set to 1, this field will contain the element address of the last storage element the media was in.
Additional Sense Code Qualifier – If the element is in an abnormal state, this field will be set to a value as described in Table 71 on page 72. Source Valid (Svalid) – This field is set to 1 if the Source Storage Element Address field is valid, otherwise it is set to 0. Invert – This field is set to 0. The library does not support inverting media.
Data Transfer Element Descriptor Table 64 Data Transfer Element Descriptor Bit Byte 7 6 5 4 3 2 1 Except Rsvd 0 0 Element Address 1 2 Reserved Access 3 Reserved 4 Additional Sense Code 5 Additional Sense Code Qualifier 6 NotBus Rsvd IDValid LUValid Rsvd 7 SCSI Bus Address 8 Reserved 9 SValid Invert Full Logical Unit Number Reserved 10 Source Element Address 11 12 47 Primary Volume Tag Information (Field omitted if PVolTag = 0; remaining fields move up) 48 Reserved C
IDValid – A value of one indicates that the SCSI Bus Address field is valid. A value of zero indicates that it is not. LUValid – This field is not supported and is set to 0. Logical Unit Number – This field is not supported and is set to 0. SCSI Bus Address – When the IDValid field is set to one, this field contains the tape drive SCSI address. This is only applicable to SCSI tape drives, and does not apply to Fibre Channel tape drives.
Release Element – 17h What the Library Does With This Command The library releases any outstanding reservation that had previously been made by the same initiator via the RESERVE command. Only whole logical unit reservations are allowed; individual element reservations are not supported. Command Usage This command should be used to release the library from any reservations previously made. Release Element CDB Format The RELEASE ELEMENT CDB format is shown in the following table.
Report LUNS – A0h What the Library Does With This Command The library will return a list of the logical units that it supports. When this command is sent to the Controller logical unit (LUN 0), it will return a list of all additional logical units that are available. This list will primarily be Media Changer devices representing the configured Logical Libraries. When this command is sent to any of the Media Changer logical units, they will only report themselves.
Report LUNS Response Table 67 Report LUNS Response Bit Byte 7 6 5 4 3 2 1 0 0 LUN List Length (n-7) 3 4 Reserved 7 8 First LUN 15 n-7 Last LUN n LUN List Length – This field returns the length in bytes of the list of LUNs being returned. LUN – These fields return each available assigned LUN. The information conforms to the Logical Unit Address Method defined in SCC-2, and supports only First Level addressing (for each LUN, only the second byte is used and contains the assigned LUN).
Request Sense – 03h What the Library Does With This Command The library returns eighteen bytes of sense data to the requesting initiator. The data is preserved until either the REQUEST SENSE command or any other command is received. The library can queue multiple Unit Attentions for processing. Command Usage This command should be issued whenever the initiator receives a CHECK CONDITION from the library. It should continue to be issued until all check conditions have been cleared.
Request Sense Response Table 69 Request Sense Response Bit Byte 0 7 6 5 4 Valid 3 2 1 0 Response Code (70h) 1 Reserved 2 Reserved Sense Key 3 Information 6 7 Additional Sense Length (0Ah) 8 Command Specific Information (0000 0000h) 11 12 Additional Sense Code (ASC) 13 Additional Sense Code Qualifier (ASCQ) 14 Field Replaceable Unit Code 15 SKSV C/D Rsvd Rsvd BPV Bit Pointer 16 Field Pointer 17 Valid – The Valid field is set to 0 if the Information field is not valid.
Information – This field returns additional information for certain ASC/ASCQs where a specific device must be identified and the sense data is associated with a Unit Attention condition instead of a specific command. These are described as follows: • If the ASC/ASCQ is related to Import/Export stations, then byte 6 indicates which I/E station it pertains to (1 to 4). • If the ASC/ASCQ is related to a specific Data Transfer Element, then bytes 5 and 6 contain the element address of that element.
Table 71 Additional Sense Codes and Qualifiers (Continued) Sense Keys ASC Description ASCQ 2 4 5 6 B 04h 83h x The library is not ready due to aisle power being disabled 04h 8Dh x The library is not ready because it is offline 08h 00h x LU Communication Failure 08h 01h x LU Communication – Timeout (only PowerVault ML6000) 08h 80h x LU Communication – SCSI Failure 08h 82h x LU Communication – SCSI Command Execution or Queuing Failure 08h 83h x LU Communication – SCSI Comma
Table 71 Additional Sense Codes and Qualifiers (Continued) Sense Keys ASC Description ASCQ 2 4 5 6 B 28h 01h x Insert/Eject station opened and closed 29h 00h x Power-on or reset occurred 29h 01h x Power on occurred 29h 03h x Device reset occurred 29h 04h x Internal reset occurred 2Ah 01h x Mode parameters have been changed 2Ah 03h x Reservations preempted 2Ah 04h x Reservations released 2Ah 05h x Registrations preempted 2Ch 00h x Command sequence error 30h 0
Table 71 Additional Sense Codes and Qualifiers (Continued) Sense Keys ASC Description ASCQ 2 4 53h 00h x 53h 01h x 53h 5 6 B A drive did not load or unload a tape x A drive did not unload a cartridge 02h x Medium removal prevented 53h 81h x Insert/Eject station door is open 53h 82h x Cannot lock the I/E station 53h 83h x Cannot unlock the I/E station 83h 00h x Label too short or too long 83h 02h x Barcode label questionable 83h 03h x Cell status and barcode label
Reserve Element - 16h What the Library Does With This Command The library reserves the entire library for the initiator making the request. Only whole logical unit reservations are allowed; individual element reservations are not supported. The reservation remains in effect until either the initiator that made the reservation sends a RELEASE command, or a reset or power-cycle of the library occurs.
Send Diagnostic - 1Dh What the Library Does With This Command If the Self Test option is requested, the library executes a pre-defined diagnostic. Command Usage This command can be used to verify the operational status of the library and its components. Send Diagnostic CDB Format The SEND DIAGNOSTIC CDB format is shown in the following table.
Test Unit Ready (00h) What the Library Does With This Command The library returns status based on its current mode and state. These are defined in the following table.
Write Buffer (3Bh) What the Library Does With This Command The library will receive a requested buffer of data and write it to the appropriate internal storage. The Controller logical unit is the primary device to use with this command, since the Media Changer logical units only support the echo buffer mode. Command Usage This command can be used primarily to download new firmware to the library, as well as to perform enhanced domain validation (using the echo buffer mode).
Buffer Offset – This field indicates the starting location (byte offset) within the specified buffer to write data. The initiator should conform to the offset boundary requirements returned in the READ BUFFER descriptor described in “Read Buffer Response.” Parameter List Length – If applicable, this field should be set to indicate the amount of data being written.
