Abstract:
A method for managing a storage subsystem including a plurality of information recording media includes selecting at least one recording medium from the plurality of information recording media to perform a service to the selected recording medium. A locating device associated with the selected recording medium is activated to identify the location of the selected recording medium in the storage subsystem.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS  
       [0001]     The present application is a continuation application of U.S. patent application Ser. No. 10/370,865, filed Feb. 19, 2003, and is related to and claims priority from Japanese Patent Application No. 2002-259519, filed on Sep. 5, 2002. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     The present invention relates to data storage system and management thereof.  
         [0003]     As noted in Japanese Patent Laid-open Publication No. 2000-305720, a hard disk drive (“HDD”) monitoring system with a graphic user interface (“GUI”) is used to manage the status of HDD. On the GUI screen, it is possible to display and monitor the following: the HDD RAID group constitution, an HDD including a designated logic unit (“LU”), the RAID group display, and the HDD failure.  
         [0004]     As noted in Japanese Patent Laid-open No. 2001-222385, technology for lighting an LED associated with the HDD to give notice of a failure is described. The LED attached to a storage device provides information about the operating status of a HDD. That is, whether the HDD is operating normally or is experiencing problem.  
         [0005]     As the number of HDDs installed in disk array devices increases, e.g., 100 or more HDDs, it has become increasingly complicated to replace problematic disks or upgrading older generation of disks. In a single disk array device or storage subsystem, virtually identical disks or HDDs are provided in a matrix of 10-20 rows by 10-20 columns. In addition, the HDDs associated with one RAID group are generally dispersed randomly within the storage device. Accordingly, there is a risk that a maintenance administrator may erroneously remove a wrong HDD and cause an unintended storage failure. Such a risk is unacceptable since the reliability of the disk array devices is paramount. Therefore, it is desirable to provide more reliable means of replacing HDDs provided in the disk array devices.  
       BRIEF SUMMARY OF THE INVENTION  
       [0006]     The present invention relates to storage devices and subsystems and management thereof. One embodiment of the present invention relates to a management method for a storage subsystem that may be implemented in existing storage subsystems without little or no additional hardware, i.e., with mostly software upgrade. Another embodiment of the present invention relates to a service processor or management agent of storage subsystems. Yet another embodiment relates to storage subsystem having locations devices to easily located disk drives to be serviced.  
         [0007]     In one embodiment, a method for managing a storage subsystem including a plurality of information recording media includes selecting at least one recording medium from the plurality of information recording media to perform a service to the selected recording medium. A locating device associated with the selected recording medium is activated to identify the location of the selected recording medium in the storage subsystem.  
         [0008]     In another embodiment, a method for managing a storage subsystem including a disk array device and a service processor coupled to the disk array device is disclosed. The disk array device includes a plurality of hard disk drives. The method includes selecting a hard disk drive provided in the disk array device; and activating a locating device associated with the selected hard disk drive to provide information about the location of the selected hard disk drive.  
         [0009]     In another embodiment, a method for managing a disk array device including a plurality of hard disk drives and a plurality of light emitting devices is described. Each hard disk device is associated with at least one dedicated light emitting device. The method includes displaying a layout map of the hard disk drives provided in the disk array device, the layout map including a plurality of disk representations corresponding to the plurality of hard disk drives provided in the disk array device; selecting one or more of hard disk drives provided in the disk array device using a service processor coupled to the disk array device; and causing one or more light emitting devices associated with the selected one or more hard disk drives to be operated differently from the light emitting devices of the hard disk drives that have not been selected, so that the selected one or more hard disk drives can be easily located in the disk array device.  
         [0010]     In yet another embodiment, a computer readable medium including code for managing a storage subsystem including a plurality of information recording media is disclosed. The computer readable medium includes code for selecting at least one recording medium from the plurality of information recording media to perform a service to the storage subsystem; and code for activating a locating device associated with the selected recording medium to provide information about the location of the selected recording medium.  
         [0011]     In yet another embodiment, a storage subsystem includes a disk array device including a plurality of hard disk drives and a plurality of light emitting devices, each hard disk drives being associated with at least one dedicated light emitting device; a disk controller coupled to the disk array device to regulate the data flow into and out of the disk array device; and a service processor coupled to the disk controller to manage the storage subsystem, the service processor including a management program that enables a selection of one or more hard disk drives provided in the disk array device that require service and activation of one or more light emitting devices associated with the selected one or more hard disk drives, wherein the one or more light emitting devices are operated differently from light emitting devices of the hard disk drives that have not been selected in order to provide information about the location of the selected one or more hard disk drives. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]      FIG. 1  illustrates a network system including a plurality of storage subsystems according to one embodiment of the present invention.  
         [0013]      FIG. 2  illustrates a display screen of a service processor that is used to examine the operating status of the HDDs in a storage subsystem according to one embodiment of the present invention.  
         [0014]      FIG. 3  illustrates a schematic configuration of a disk array device and a service processor according to one embodiment of the present invention.  
         [0015]      FIG. 4  shows a process for servicing a disk array device according to one embodiment of the present invention.  
         [0016]      FIG. 5  illustrates an exemplary window for selecting a RAID group using a graphic user interface (“GUI”) according to one embodiment of the present invention.  
         [0017]      FIG. 6  illustrates an exemplary window showing a RAID group layout diagram showing HDDs that have been selected according to one embodiment of the present invention.  
         [0018]      FIG. 7  illustrates a plurality of HDDs provided within a cabinet of a disk array device according to one embodiment of the present invention.  
         [0019]      FIG. 8  illustrates an exemplary a window for indicating the LED lighting and blinking method according to one embodiment of the present invention.  
         [0020]      FIG. 9  illustrates a schematic diagram of a disk array device with LEDs caused to blink using the window of  FIG. 8  to facilitate servicing of the disk array device according to one embodiment of the present invention.  
         [0021]      FIG. 10  is a flowchart showing a method of servicing a disk array device using a GUI display screen according to one embodiment of the present invention.  
         [0022]      FIG. 11  shows a disk array device having organic EL displays and speakers to facilitate servicing of the disk array device according to one embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0023]      FIG. 1  schematically illustrates a network system  50  including one or more messaging networks  52  and a storage area network (“SAN”)  54  connecting a plurality of servers  56  to a plurality of storage devices or subsystems  70 . The network  52  may be a local area network, a wide area network, the Internet, or the like. The network  52  enables, if desired, the storage devices  70  to be centralized and the servers  56  to be clustered for easier and less expensive administration. As used herein, the term “storage subsystem” refers to a storage unit having an integrated collection of one or more storage controllers and one or more storage components (e.g., disk drives) configured to store information.  
         [0024]     The SAN  54  supports direct, high-speed data transfers between servers  56  and storage devices  70  in various ways. Data may be transferred between the servers and storage devices. A particular storage device may be accessed serially or concurrently by a plurality of servers. Data may be transferred between servers. Alternatively, data may be transferred between the storage devices  70 , which enables data to be transferred without server intervention, thereby freeing server for other activities. For example, a storage device may back up its data to another storage system at predetermined intervals without server intervention.  
         [0025]     Accordingly, the storage devices or subsystems  70  is not dedicated to a particular server bus but is attached directly to the SAN  44 . The storage subsystems  70  are externalized and functionally distributed across the entire organization.  
         [0026]     In one embodiment, the SAN  54  is constructed from storage interfaces and is coupled to the network  52  via the servers  56 . Accordingly, the SAN may be referred to as the network behind the server or sub-network.  
         [0027]     The network system  50  also includes a service processor or management agent  74  coupled to the SAN according to one embodiment of the present invention. The service processor  74  is a data processing system, e.g., a computer, that is used to monitor the operating status of the storage subsystem and HDDs provided therein and also to perform other management related functions, such as replacing or upgrading HDDs. The service processor  74  includes a display area that provides a graphic user interface (“GUI”) that a network administrator can use to manage the storage subsystem.  
         [0028]     In one embodiment, the storage device or subsystem  70  is a disk array device including one or more hard disk drives (HDDs) and a disk controller (or a storage controller) that controls the data flow into and out of the disk drives. The service processor  74  is generally coupled to the disk controller. In one embodiment, the service processor is a notebook computer and provided within the same housing as where the disk controller is provided. Accordingly, the service processor  74  may be seen as being included in the storage subsystem  70 . However, the service processor is illustrated apart from the storage subsystem  70  in  FIG. 1  for purpose for describing the present embodiment. Although the storage subsystem  70  has been described using the SAN environment, it may be provided in other network environment, e.g., a network area storage (NAS) environment.  
         [0029]      FIG. 2  illustrates a display screen  62  of the service processor  74  that is used to examine the operating status of the HDDs in a storage subsystem according to one embodiment of the present invention. The display screen includes a Redundant Array of Inexpensive Disks (“RAID”) group selection region  64 , a RAID group constitution region  66 , and a RAID group layout region  68 , and an LED control region.  
         [0030]     The RAID group selection region  64  is a region where it is possible to select and designate a RAID group. The RAID group selection region  64  is shown in  FIG. 5 , for example, and is explained below with reference to  FIG. 5 . The RAID group constitution region  66  provides information regarding the HDDs constituting the selected RAID group using the RAID group selection region  64 . For example, as shown in  FIG. 5 , when the RAID group RAID-Group- 0005  is selected in the RAID group selection region  64 , the RAID group constitution region  66  indicates that the RAID-Group- 0005  comprises four disks and one parity disk, as shown in  FIG. 2 .  
         [0031]     The RAID group layout region  68  displays the layout of the plurality of HDDs in the disk array device  70 . The maintenance staff can easily monitor the status of these HDDs by referring to the RAID group layout region  68 . A more detailed view of the RAID group layout region  68  is shown in  FIG. 6 . When a specific RAID group is selected and designated in the selection region  64  by the maintenance staff, the HDDs included in the selected RAID group are highlighted or shown differently from other HDDs, e.g., shown as the shaded HDD blocks  324 , in the layout region  68 , as will be explained in more details later using  FIG. 6 .  
         [0032]     The LED control region  410  is used to display the lighting and blinking method of the LED. The LED control region  410  is shown in  FIG. 8 , for example, and is explained below with reference to  FIG. 8 .  
         [0033]      FIG. 3  illustrates a schematic configuration of the disk array device  70  and SVP  74 . The disk array device  70  comprises a disk or storage controller  71  and a disk array  72 . The disk controller  71  controls or regulates information being exchanged between a remote device and the disk array  72 . The disk controller  71  comprises a processor  75 , a switch  76 , a shared memory  77 , a channel adapter (“CHA”)  78 , a disk adapter (“DKA”)  79 , and a SVP connection adapter  80 . The processor  75  is connected to the switch  76 , memory  77 , CHA  78 , and SVP connection adapter  80 . The processor controls the disk controller  71  and the information being processed therein. The switch  76  is connected to the processor  75  and a plurality of DKAs  79  to enable information to be communicated between these devices. The memory  77  contains a RAID group-HDD correspondence table  82 .  
         [0034]     The table  82  includes information associating RAID groups to the HDDs, so that data can be route to appropriate storage locations. For example, a row or record  83  in the table  82  indicates that the RAID group  0005  includes or is associated with the HDDs  121 ,  122 ,  123   124 , and  125 . These HDD numbers  121 - 125  are HDD identification numbers that are assigned to each HDD by the DKA  79  or the like. Generally sequential numbers are used as the identification numbers for convenience. Instead of the memory  77 , the correspondence table  82  may be provided on a system disk according to one embodiment. Such a system disk generally includes control information used for the operation of the processor  75 . If also provided for the disk controller  71 , one or more of the HDDs in the disk array  72  may be used as system disks.  
         [0035]     The CHA  78  is connected to the SAN  54  and converts and relays information to be sent and received between the server  56  and disk controller  71  through the SAN  54 . The DKA  79  is connected to the disk array  72  and converts and relays information to be sent and received between the disk controller  71  and the disk array  72 . The SVP connection adapter  80  is connected to the SAN  54  and converts and relays information to be sent and received between the SVP  74  and the disk controller  71  via the SAN  54 . In some embodiments, the SVP  74  is coupled to the disk controller  71  via a local area network (“LAN”), as shown in  FIG. 1  The SVP  74  comprises an input device or means  61 , such as a keyboard, mouse, or touchpad, a display screen  62 , and a storage management program  84  used for managing the HDDs in the disk array  70 . The storage management program  84  communicates with the disk controller  71  and displays graphic user interface (“GUI”) information on the display screen  62 , such as that shown in  FIG. 2 .  
         [0036]     The disk array  72  comprises a plurality of HDDs  402  and an LED mounting portion  404 . The plurality of HDDs  402  is connected to the DKA  79  using a fiber channel arbitrated loop or the like and performs data transferring with the DKA  79 . The LED mounting portion  404  is connected to the DKA  79  using a signal line; a plurality of LEDs is mounted thereon. The LED mounting portion  404  executes the lighting and blinking of the LEDs mounted thereon, as controlled by the processor  75  according to one embodiment of the present invention.  
         [0037]      FIG. 4  is a flowchart  100  illustrating a method of replacing HDDs in the storage subsystem  70  using the service processor  74  according to one embodiment of the present invention. At first, a storage administrator (or maintenance staff) decides that HDDs in a RAID group need to be replaced (step  101 ). For example, the administrator may wish to replace the HDDs with those having greater capacity or because one or more of the HDDs are experiencing failure.  
         [0038]     The maintenance staff selects a pertinent RAID group on the display screen  62  of the SVP  74 , operating in a GUI environment, using the input means  61  (Step  102 ). The selection is made on the RAID group selection region  64 , shown in  FIG. 5 . For example, the RAID-Group- 0005  is selected using the selection region  64 . In one embodiment, the RAID group list is displayed when the list display button, on the RAID group selection region  64 , is pressed using the input means  61 , and then the pertinent RAID group is selected from the displayed list.  
         [0039]      FIG. 6  illustrates an exemplary RAID group layout region  68 . A layout  323  including 10 columns by 10 rows of blocks represents the HDDs provided in the disk array device  70 . The blocks corresponding to the HDDs in the RAID-Group- 0005  that has been selected above are indicated as numerals  324  and differentiated from other HDDs by displaying the former as shaded blocks. The HDDs  324  comprise 4 data disks and 1 parity disk corresponding to the information provided on the constitution region  66 .  
         [0040]     As shown, the HDDs  324  are randomly distributed within the disk array device, which complicates the HDD replacement procedure since it would not be easy for the maintenance staff to memorize their exact locations. Consequently, there is a risk that the maintenance staff may erroneously replace a wrong disk and cause a system failure.  
         [0041]     One possible solution would be to print the layout map illustrated in  FIG. 6  as a reference sheet. However, the storage subsystem may not be provided with a printer. Even with a printed layout map, the replacement operation involves some risk since the disk array device may have 100 or more HDDs that all look substantially identical in a matrix of 10 by 10, or 10 by 20. If a wrong HDD is removed, the system failure or data loss may result, which are highly undesirable since reliability is paramount in the storage technology.  
         [0042]     Generally, the disk array device includes a plurality of storage cabinets provided in a vertical alignment. That is, a row of the layout map  323  represents a single storage cabinet. Accordingly, a disk array device having HDDs in a matrix of 10 by 10 has ten storage cabinets that are vertically aligned to each other.  
         [0043]     Referring back to the process  100 , after step  103 , the maintenance staff, on the display screen  62  of the SVP  74 , causes the LEDs corresponding to the selected HDDs  324  to emit light in a certain way to differentiate them from the LEDs of other HDDs (Step  104 ).  
         [0044]      FIG. 7  illustrates a storage cabinet  400  including a plurality of HDDs  402  and an LED section or mounting portion  404 . The LED section  404  includes a plurality of LEDs  401   a  and  401   b  that indicate the operating status of the HDDs. For example, the LED section  404  includes for each HDD a first LED  401   a  to indicate whether the corresponding HDD is active and a second LED  401   b  to indicate whether the corresponding HDD is experiencing failure. The LED section  404  may be provided on the housing of the storage cabinet or on the housing of each of the HDD.  
         [0045]     In one embodiment, the LED  401   a  emits green lights when the power is on; the corresponding LED  401   a  blinks when the HDD  402  is being accessed. The corresponding LED  401   b  emits red light when the corresponding HDD is experiencing problem. In step  104  in  FIG. 4 , the HDDs  324  are differentiated from other HDDs by causing their LEDs to blink. For example, both of the LEDs  401   a  and  401   b  are caused to blink at the same time. Alternatively, the LEDs  401   a  and  401   b  may blink one of at time, or one LED may blink twice after the other blinks once. In another embodiment, the LED mounting portion  404  includes a third LED  412  for each HDD. The LED  412  is caused to emit light when the corresponding HDD is selected using the selection region  64 . The above blinking controls can be made using a GUI environment, i.e., the LED control region  410 , provided by the SVP  74 .  
         [0046]      FIG. 8  shows the LED control region  410  displayed on the display screen  62  of the SVP  74 . An embodiment of making the instructions regarding the LED display is explained next using  FIG. 8 . The maintenance staff uses the input means  61  and indicates the lighting and blinking method for the LEDs  401   a  and  401   b  displayed on the LED control region  410 . For example, the maintenance staff selects blinking method for the LED  401   a,  instructs the blinking time for both on and off states to be 0.5 seconds, and the start time to be 0 seconds. Similarly, the LED  401   b  is caused to blink in a particular way, i.e., the blinking time is 0.5 seconds. In order for these LEDs to blink alternately, the start times for each is offset 0.5 second. In one embodiment, a default blinking method is used when a given RAID group is selected for maintenance and step  104  is not performed.  
         [0047]     Once the LED blinking method has been selected, an appropriate program causes the LEDs  401   a  and  401   b  corresponding to the HDDs of the selected RAID to blink accordingly (Step  105 ). In one embodiment, this function is performed by a program stored in the processor  75  or in a processor mounted in the CHA  78 . The storage management program  84  of the SVP  74  fetches the instructions regarding LED lighting and blinking through the input means  61  and LED control region  410  on the display screen  62 , and notifies the processor  75  in the disk controller  71  of the information relating to such instructions. The processor  75  in the disk controller  71  fetches information related to instructions regarding the LED lighting and blinking and sends a control signal regarding LED lighting and blinking to the LED mounting portion  404  through the DKA  79  in the disk controller  71 . The LEDs installed in the LED mounting portion  404  light and blink according to the control signal for LED lighting and blinking.  
         [0048]     The LEDs corresponding to an HDD group included in a designated RAID group on an actual machine are caused to be displayed, so as to be differentiated from LEDs corresponding to other HDD groups. Therefore, the maintenance staff can replace the desired HDDs according to the LED lighting and blinking method (Step  106 ). In this way, the maintenance staff is prevented from erroneously removing wrong HDDs, as can be appropriated from  FIG. 9 .  
         [0049]      FIG. 9  illustrates a disk array device  70  including LEDs corresponding to the HDD layout  323  of in  FIG. 6 . The disk array device  70  comprises a plurality of HDDs  402  including HDDs  224  corresponding to the selected HDDs blocks  324  in  FIG. 6 . The LEDs of the HDDs  224  are blinking according to the controls set on the LED control region  410 . Consequently, the maintenance staff easily identifies the HDDs  224  and performs the HDD replacement operation without mistakes.  
         [0050]      FIG. 10  illustrates a process  800  for operating the storage management program  84  of the SVP  74 . The storage management program  84  requests layout information for HDDs in the disk array device  70  from the disk array controller  71  through the SVP connection adapter  80 . The processor  75  in the disk array controller  71  collects the HDD layout information using the DKA  79  or the like and transmits the information to the storage management program  84 . This HDD layout information includes the total number of RAID groups in the disk array device  70  and/or information of the constitution of each of the RAID groups. When the storage management program  84  receives the HDD layout information, the layout is displayed on the display screen  62  (Step  801 ). The display screen  62  includes the RAID group selection region  64 , the RAID group constitution region  66 , and the RAID group layout region  68 . Next, the storage management program  84  determines whether or not a device subject to operation (e.g., a RAID group) is selected on the RAID group selection region  64  (Step  802 ). In one embodiment, one or more HDDs may be selected directly including those in different RAID groups.  
         [0051]     When a device subject to operation is designated on the RAID group selection region  64 , the storage management program  84  requests information regarding the device subject to operation from the disk controller  71 . For example, as shown in  FIG. 5 , when the RAID-Group- 0005  in the RAID group selection region  64  is selected by the maintenance staff, the storage management program  84  requests layout information for the HDDs included in the RAID-Group- 0005  from the disk controller  71 . The processor  75  in the disk controller  71  accesses the RAID group-HDD correspondence table  82  and provides the HDD layout information to the storage management program  84 .  
         [0052]     Upon receipt of the HDD layout information, the storage management program  84  determines (or is informed) that the HDDs associated with the RAID-Group- 0005  are HDDs  121 - 125 . The storage management program  84  displays the HDD numbers  121 - 125  as shaded blocks on the RAID group layout region  68  to differentiate them from other HDD blocks (Step  803 ). The shaded layout blocks  324  are shown in  FIG. 6 .  
         [0053]     The storage management program  84  displays a screen for designating the LED display mode (Step  804 ). The screen for designating the LED display mode is the LED control region  410  shown in  FIG. 9 ; and the LED blinking mode is selected by the maintenance staff. The storage management program  84  determines whether or not the LED blinking mode has been selected (Step  805 ). If the display mode has not been selected within a given time period, a default display mode is implemented (Step  806 ). The storage management program  84  transmits the display mode information to the disk controller  71 . The processor  75  in the disk controller  71  receives the display mode information and causes the LEDs to blink accordingly (Step  807 ).  
         [0054]     Using the storage management program  84 , the LEDs provided at a close proximity to the HDDs can be controlled to emit light accordingly to the instructions from the maintenance staff as discussed above.  
         [0055]     In another embodiment, a display device is provided on the housing of the storage cabinet, rather than LEDs, to identify the selected HDDs. For example, an organic electroluminescent display  701  is provided for each HDD. The display  701  provides the maintenance staff with a greater flexibility in the methods used to identify the selected HDDs since words, symbols, or pictures may be displayed on the display  701 . As a secondary or precautionary tool, a speaker  702  may be provided on the storage cabinet or the disk array device to provide verbal instructions in addition to the visual aid provided by the display  701 .  
         [0056]     Alternatively, the speaker  702  may be used as a primary tool in identifying the selected HDDs. For example, each HDD is provided with a unique identification number and the speaker states the identification number of the selected HDDs to assist the maintenance staff in safely locating the HDDs.  
         [0057]     The above embodiments also may be used to remove and insert HDDs in a particular order if such a procedure is desired. In such a case, HDDs are inserted in an add-on cabinet, for example. HDDs having a SCSI enclosure service function and an enclosure service interface function must be inserted in advance of other HDDs. This is because communication between the base cabinet and the add-on cabinet becomes possible with these HDDs as communication terminals when HDDs having these functions are inserted first. For these situations, the LEDs of selected HDDs are caused to blink in a given order using the display screen  62 . For example, only the LEDs of the HDD to be removed first are caused to blink initially. Once this HDD has been removed, the LEDs of the next HDD to be removed are caused to blink, so on. If the display  701  is used, the display may show the order of HDD removal using sequential numbers for each of the selected HDDs.  
         [0058]     The above detailed descriptions are provided to illustrate specific embodiments of the present invention and are not intended to be limiting. Numerous modifications and variations within the scope of the present invention are possible. For example, in one embodiment, the RAID group-HDD correspondence table  82  is provided within the SVP  74 . The embodiment of the present invention may be used for storage components other than RAID groups, including logical units (“LU”), one or more HDDs, a HDD group included in a LU, and one or more RAID groups in a LU. The embodiments of the present invention can also be used to transport one or more HDDs in from one disk array device  70  to another disk array device  70 . In such a case, the LEDs corresponding to the both source and destination locations may be caused to blink accordingly. Accordingly, the present invention is defined by the appended claims.