Abstract:
The invention provides a management system solving the problems of the storage area network shared among plural devices, which was incapable of guaranteeing communication performances due to varied response time, and which required unstable time for accessing volumes.  
     The storage area network management system comprises plural information processing devices  21 , plural storage devices  41 , a network with plural network equipments  31  to which is configured a network bandwidth used for communication between information processing devices  21  and storage devices  41 , and a management device  1 , wherein management device  1  comprises a data storage device  10  for storing a connection structure information and a performance information of paths of the network equipments  31  and a performance information and a capacity information of storage devices  41 , and a storage selection means  13  for selecting a storage device  41  for allocating a volume to information processing device  21 , and upon allocating a volume to information processing device  21 , storage selection means  13  selects, based on the information stored in data storage device  10 , storage device  41  fulfilling the performance and the volume capacity required by information processing device  21  and also having on its path network equipment  31  to which is configured the network bandwidth required for the communication with information processing device  21.

Description:
[0001]     The present application is based on and claims priority of Japanese patent application No. 2004-263226 filed on Sep. 10, 2004, the entire contents of which are hereby incorporated by reference.  
       BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates to a method for allocating a volume to an information processing device in a storage area network.  
         [0004]     2. Description of the Related Art  
         [0005]     Storage devices connected to a network, so-called network storage devices, are utilized via a network by information processing devices. Network storage devices communicate with the information processing devices according to the protocol of the connecting network. There are various types of such networks, one of which is an IP (internet protocol) network.  
         [0006]     Plural devices are connected to the IP network, and these devices share the network and communicate via the network simultaneously. Therefore, when a large amount of traffic occurs, communication data may be lost, or communication may be delayed. Thus, in a storage area network, the performance of the information processing device to access the volume allocated thereto is deteriorated, and it becomes impossible to exert the best performance of the storage devices.  
         [0007]     In order to solve this problem, patent document 1 discloses a method for selecting the storage device for allocating the volume based on the response time and the number of network equipments between the information processing device and storage device when allocating a volume to the information processing device.  
         [0000]     [Patent Document 1] 
         [0008]     Japanese Patent Laid-Open Publication No. 2003-140930  
       SUMMARY OF THE INVENTION  
       [0009]     However, as described, since the IP network is shared by plural devices, the response time varies constantly. Therefore, it is not possible to guarantee the communication performance merely by response time and number of hops. Moreover, since the bandwidth enabling access from the information processing device to the volume is not guaranteed, the time required for accessing the volume may be unstable.  
         [0010]     In order to solve the problems of the prior art, the present invention provides, in a storage area network using network equipments capable of guaranteeing the bandwidths to be used for every device performing communication through the network, a management device equipped with a data storage device for storing the information on the bandwidths of each network equipment and the reserved bandwidths, the connection structure of the network equipments and the information on the information processing devices and the storage devices connected to the storage area network, the management device being connected to the network equipments, the information processing devices and the storage devices. The management device is equipped with a first means for selecting the storage device that fulfils the performance of the storage device and the volume capacity required by the information processing device and that enables connection reserving the network bandwidth required by the information processing device, a second means for sending an instruction to the storage device to create the storage device a volume with a capacity required by the information processing device and to allocate the volume to the information processing device, and a third means for reserving the bandwidth required by the information processing device to the network equipment.  
         [0011]     In other words, the present invention relates to a storage area network comprising: a plurality of information processing devices; a plurality of storage devices; a storage area network having the information processing devices and the storage devices connected thereto, and further having network equipments, each network equipment having configured thereto a network bandwidth used for communication between the information processing devices and the storage devices; and a management device connected to the information processing devices, the storage devices and the storage area network for management; wherein the management device comprises a data storage device for storing a connection structure information and a performance information of paths of the network equipments and a performance information and a capacity information of the storage devices, and a storage selection means for selecting a storage device for allocating a volume to the information processing device, and upon allocating a volume to the information processing device, the storage selection means selects, based on the information stored in the data storage device, the storage device having the performance and the volume capacity required by the information processing device and also having on its path the network equipment to which is configured the network bandwidth required for the communication with the information processing device.  
         [0012]     According further to the present invention, the management device is equipped with an allocation instruction means for instructing the selected storage device to create a volume and to allocate the same to the information processing device, and the allocation instruction means sends to the storage device selected by the storage selection means an instruction to create the volume having the capacity required by the information processing device and an instruction to allocate the created volume to the information processing device.  
         [0013]     According to the present invention, the management device comprises a configuration instruction means for instructing the network equipment constituting the path to configure the network bandwidth used by the information processing device and the selected storage device, and the configuration instruction means selects, based on the information stored in the data storage device, the network equipment connecting the information processing device and the storage device allocating the volume to the information processing device, and instructs the selected network equipment to configure the network bandwidth required by the information processing device.  
         [0014]     The storage area network management system of the present invention further comprises an adjustment selection means, wherein when the storage selection means selects the storage device for allocating the volume, if there is a storage device fulfilling the storage device performance and the volume capacity required by the information processing device but there is no network equipment having configured thereto the network bandwidth required for the communication between the information processing device and the storage device, the adjustment selection means reduces the network bandwidth of the network equipment already configured between the information processing device and the storage device to volume units that have already been allocated, adjusts the network bandwidth between the information processing device and the storage device, and selects the storage device having reserved the network bandwidth for the newly allocated volume as the storage device for allocating the volume.  
         [0015]     According further to the present storage area network management system, the management device comprises an output device and an input device, wherein when the storage selection means selects a plurality of storage devices, outputs to the output device information on the available capacity and performance of the selected plurality of storage devices and the available bandwidth of the network between the information processing device, and determines the storage device selected and instructed by the input device based on the information output to the output device to be the storage device for allocating the volume to the information processing device.  
         [0016]     Further, the present invention provides a management device connected to and managing a plurality of information processing devices, a plurality of storage devices, and a storage area network having the information processing devices and the storage devices connected thereto, and further having network equipments, each network equipment having configured thereto a network bandwidth used for communication between the information processing devices and the storage devices, wherein the management device comprises a data storage device for storing a connection structure information and a performance information of paths of the network equipments and a performance information and a capacity information of the storage devices, and a storage selection means for selecting a storage device for allocating a volume to the information processing device, and upon allocating a volume to the information processing device, the storage selection means selects, based on the information stored in the data storage device, the storage device having the performance and the volume capacity required by the information processing device and also having on its path the network equipment to which is configured the network bandwidth required for the communication with the information processing device.  
         [0017]     Further, the present invention provides a volume allocation method for a storage area network management system comprising a plurality of information processing devices; a plurality of storage devices; a storage area network having the information processing devices and the storage devices connected thereto and further having network equipments, each network equipment having configured thereto a network bandwidth used for communication between the information processing devices and the storage devices; and a management device connected to the information processing devices, the storage devices and the storage area network for management; the volume allocation method comprising: storing a connection structure information and a performance information of paths of the network equipments and a performance information and a capacity information of the storage devices; and selecting, based on the information stored in the data storage device, a storage device having the performance and the volume capacity required by the information processing device and also having on its path the network equipment to which is configured the network bandwidth required for the communication with the information processing device, for selecting the storage device for allocating the volume to the information processing device.  
         [0018]     The volume allocation method according to the present invention further comprises instructing the selected storage device to create a volume with a capacity required by the information processing device, and sending to the selected storage device an instruction to allocate the created volume to the information processing device.  
         [0019]     Moreover, the volume allocation method according to the present invention further comprises selecting, based on the information stored in the data storage device, the network equipment connecting the information processing device and the storage device allocating the volume to the information processing device, and instructing the selected network equipment to configure the network bandwidth required by the information processing device.  
         [0020]     Even further, the volume allocation method according to the present invention further comprises upon selecting the storage device for allocating the volume, if there is a storage device fulfilling the storage device performance and the volume capacity required by the information processing device but there is no network equipment having configured thereto the network bandwidth required for the communication between the information processing device and the storage device, adjusting the network bandwidth between the information processing device and the storage device by reducing the network bandwidth of the network equipment already configured between the information processing device and the storage device to volume units that have already been allocated; and selecting the storage device having reserved the network bandwidth for the newly allocated volume to be the storage device for allocating the volume.  
         [0021]     Furthermore, the volume allocation method according to the present invention comprises, when a plurality of storage devices are selected, outputting to the output device information on the available capacity and performance of the selected plurality of storage devices and the available bandwidth of the network between the storage devices, and determining the storage device selected and instructed by the input device based on the information output to the output device as the storage device for allocating the volume to the information processing device.  
         [0022]     The present invention also provides a computer software used in a management device for a storage area network management system comprising a plurality of information processing devices; a plurality of storage devices; a storage area network having the information processing devices and the storage devices connected thereto and further having network equipments, each network equipment having configured thereto a network bandwidth used for communication between the information processing devices and the storage devices; and a management device connected to the information processing devices, the storage devices and the storage area network for management; the computer software being a program for realizing the following functions in a computer: a function for storing a connection structure information and a performance information of paths of the network equipments and a performance information and a capacity information of the storage devices; and a function for selecting, based on the information stored in the data storage device, a storage device having the performance and the volume capacity required by the information processing device and also having on its path the network equipment having configured the network bandwidth required for the communication with the information processing device, in order to select the storage device for allocating the volume to the information processing device.  
         [0023]     According to the present invention, the storage device for allocating the volume is selected not only based on the capacity of the allocatable volume in the storage network but also based on the vacant bandwidth of the path for connecting the storage device and the information processing device. Therefore, it enables volume to be allocated easily to the information processing device. Further, since the bandwidth between the information processing device and the storage device is guaranteed, it prevents deterioration of performance of the service provided by the information processing device and also enables to exert the maximum performance of the storage device. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0024]      FIG. 1  is a drawing showing in simplified form the configuration of the storage area network management system of the present embodiment;  
         [0025]      FIG. 2  is a drawing showing an example of the data layout of a storage device management information;  
         [0026]      FIG. 3  is a drawing showing an example of the data layout of a server management information;  
         [0027]      FIG. 4  is a drawing showing an example of the data layout of a network equipment management information;  
         [0028]      FIG. 5  is a drawing showing an example of the data layout of a path information;  
         [0029]      FIG. 6  is an example of the data layout of a volume allocation information;  
         [0030]      FIG. 7  is an example of the process flow of a volume allocation program;  
         [0031]      FIG. 8  is an example of the process flow by the volume allocation program for selecting a storage device for allocating the volume;  
         [0032]      FIG. 9  is an example of the process flow by the volume allocation program for generating the volume in the storage device and allocating the same;  
         [0033]      FIG. 10  is an example of the process flow by the volume allocation program for reserving the bandwidth of a network equipment that connects the server and storage device;  
         [0034]      FIG. 11  is an example of the layout of data sent and received between the volume allocation program and the server or network equipments;  
         [0035]      FIG. 12  is an example of the layout of a volume condition entry screen;  
         [0036]      FIG. 13  is an example of the layout of a confirmation screen for confirming whether to search again for a volume;  
         [0037]      FIG. 14  is an example of the layout of a storage device select screen;  
         [0038]      FIG. 15  is an example of the layout of a volume allocating screen;  
         [0039]      FIG. 16  is an example of the layout of a volume allocation complete screen;  
         [0040]      FIG. 17  is an example of the layout of a bandwidth adjustment confirmation screen;  
         [0041]      FIG. 18  is an example of the layout of a bandwidth adjustment screen; and  
         [0042]      FIG. 19  is an example of the process flow by the volume allocation program for adjusting the bandwidth to be used for communication between the server and storage device. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0043]     The preferred embodiments for carrying out the present invention will be described.  
         [0044]     The preferred embodiments of the system and device for managing the storage area network and volume allocation method according to the present invention will now be described with reference to the drawings.  
       Embodiment 1  
       [0045]     Embodiment 1 will be described.  FIG. 1  illustrates an example of the configuration of a storage area network management system according to the present embodiment. A management device according to the present embodiment is equipped with a storage selection means, an allocation designation means, a configuration designation means and an adjustment selection means. Actually, in  FIG. 1 , the management device  1  is equipped with a central processing unit (CPU)  8 , an output unit  6 , an input unit  7 , a memory  9 , a structure information  10  and a network communication unit  11 , which are connected via a bus  12 . Only a single bus is illustrated in  FIG. 1  for sake of simplicity, but plural buses can be used. Memory  9  stores a volume allocation program  13  that realizes the volume allocation method according to the storage area network management system of the present embodiment, and a communication control program  14 . The communication control program  14  carries out the communication process by a communication protocol of a management network  2 . This communication process corresponds to a TCP/IP process in an IP network. The volume allocation program  13  communicates via the communication control program  14  with servers  21  through  24 , network equipments  31  through  38  and storage devices  41  through  45  respectively connected to the management network  2 , to allocate volumes of storage devices  41  through  45  to the servers  21  through  24  and to configure the bandwidth to be used to the network equipments  31  through  38 . The CPU  8  reads and executes the programs stored in the memory  9  according to parameters entered through a keyboard  5  connected to the input unit  7 , and displays the result on a display unit  4  connected to the output unit  6 . Structure information  10  stores information on storage devices  41  through  45 , information on servers  21  through  24 , information on network equipments  31  through  38 , and information on the paths connecting the servers  21  through  24  and storage devices  41  through  45 .  
         [0046]     Reference number  3  denotes a storage area network (hereinafter called SAN) including network equipments  31  through  38 . The network equipments  31  through  38  are capable of reserving the bandwidths to be used by the servers  21  through  24  and storage devices  41  through  45 . Each of the network equipments  31  through  38  are connected to the management network  2  either directly or, indirectly via other network equipments. In  FIG. 1 , SAN  3  is illustrated as if it is directly connected to the management network  3  for sake of simplicity. Servers  21  through  24  are connected to the SAN  3  via network equipments  31  through  33 . Storage devices  41  through  45  are connected to the SAN  3  via network equipments  36  through  38 . Servers  21  through  24  can utilize the volumes of storage devices  41  through  45  via SAN  3 . There is no limitation to the number of servers, the number of storage devices and the connection configuration and number of network equipments constituting the SAN.  
         [0047]     Next, the details of the data stored in the structure information  10  referred to by the volume allocation program  13  will be described with reference to  FIGS. 2 through 6 .  FIG. 2  shows one example of a storage device management information  100  indicating the information related to storage devices  41  through  45  connected to SAN  3  stored in the structure information  10 . The volume allocation program  13  refers to the storage device management information  100  and selects from the storage devices  41  through  45  candidates for allocating the volume to the servers  21  through  24 . The storage device management information  100  is composed of a name  101  for identifying each storage device, a capacity  102  indicating the capacity of each storage device, a remaining capacity  103  indicating the remaining available capacity of each storage device, a connected NW equipment  104  for identifying the network equipment to which each storage device is connected, a port  105  indicating the connected port of the network equipment, an IOPS  106  indicating the number of inputs and outputs per second the storage device is capable of executing, and a remaining IOPS  107  indicating the IOPS that have not been reserved for use. Reference numbers  100   a  through  100   e  refer to records of storage devices  41  through  45  stored in the storage device management table  100 . For example, it is shown by name  101  that record  100   a  stores information related to Storage  41 . It can be seen that regarding Storage  41 , the capacity is  1800 , the remaining capacity is  300 , the network equipment to which it is connected is SW  37 , the connection port is  21 , the IOPS is  1500  and the remaining IOPS is  1000 .  
         [0048]      FIG. 3  shows one example of a server management information  200  indicating the information on the servers  21  through  24  connected to SAN  3  stored in the structure information  10 . The server management information  200  is composed of a name  201  for identifying the servers  21  through  24 , a connected NW equipment  202  indicating the network equipments to which the servers  21  through  24  are connected, and a connection port  203  indicating the port of the network equipment to which the servers are connected. Reference numbers  200   a  through  200   d  refer to records indicating information on servers  21  through  24  stored in the server management information  200 . For example, reference number  200   a  shows that name  201  corresponds to the record storing information related to Server  21 , and that Server  21  is connected to port  11  of network equipment SW 31 .  
         [0049]      FIG. 4  shows one example of a network equipment management information  300  indicating information on network equipments  31  through  38  constituting the SAN  3  stored in the structure information  10 . The network equipment management information  300  is composed of a name  301  for identifying the network equipments, a port  302  used for communication with other equipments, a bandwidth  303  indicating the maximum bandwidth of the port identified in port  302 , a remaining bandwidth  304  indicating the unused bandwidth of the port identified in port  302 , and a connected equipment name  305  identifying the equipment connected to the port identified in port  302 . Reference numbers  300   a  through  300   k  indicate records related to network equipments  31  through  34  stored in the network equipment management information  300 . For example, record  300   a  is a record storing information related to network equipment whose name  301  is SW 31 , indicating that the maximum bandwidth of port  11  is  1500 , the remaining bandwidth is  1300 , and the equipment being connected is Server  21 . Moreover, from record  300   b , it can be seen that the network equipment SW 31  has a port  21  whose maximum bandwidth is  1500 , remaining bandwidth is  1300  and to which is connected SW 34 .  
         [0050]      FIG. 5  shows one example of a data layout of a path information  400  stored in the structure information  10  indicating the path between the server and storage device. The path information  400  is composed of a path information  401  storing the names of the server and storage device for showing which record indicates the path between which server and storage device and the remaining bandwidth of that path, a path name  402  for identifying the path, a network equipment  403  indicating the network equipments constituting the path, and used port  404  indicating the ports used for the path. Reference numbers  400   a  through  400   c  indicate examples of path records stored in the path information  400 . For example, as shown in path information  401 , record  400   b  is a record related to the path between Server  21  and Storage  42  and has a remaining bandwidth of xxxx, and as indicated in path name  402 , the name of the path is Route 2 . Further, based on network equipment  403 , it can be seen that the network equipments constituting the path Route 2  are SW 31 , SW 34  and SW 37 . Further, based on used port  404 , it can be seen that SW 31  uses ports  11  and  22 , SW 34  uses ports  11  and  21 , and SW 37  uses ports  11  and  22 .  
         [0051]      FIG. 6  shows one example of a data layout of volume allocation information  500  indicating information on the allocated volume in the paths of each record in the path information  400  shown in  FIG. 5 . The volume allocation information  500  is composed of a path name  501  used to identify the record of the path information  400 , a volume identifier  502  for identifying the volume allocated to each path, a bandwidth  503  indicating the bandwidth of the network allocated to use the volume, and an IOPS  504  indicating the IOPS of the storage device allocated for use of the volume. Reference numbers  500   a  through  500   d  show examples of records stored in the volume allocation information  500 . For example, records  500   a  and  500   b  are records related to path Route 1  as indicated in path name  501 , and it can be seen from volume identifier  502  that volumes LU 01  and LU 02  are allocated to Route 1 . Further, it can be seen from bandwidth  503  and IOPS  504  that the bandwidth of the network used by volume LU 01  is  100  and the IOPS of the storage device is  100 , and that the bandwidth of the network used by volume LU 02  is  80  and the IOPS of the storage device is  150 .  
         [0052]     Next,  FIGS. 7 through 19  are referred to in describing an example of the procedure of the volume allocation program  13  that realizes the volume allocation method in the storage area network management system according to the present embodiment.  FIG. 7  is a process flow for allocating the volumes according to the volume allocation program  13 . In step  601 , the volume allocation program  13  displays on an output device a volume condition entry screen  1100  for entering the conditions of the volume to be allocated to the server.  FIG. 12  shows an example of the volume condition entry screen  1100 . The volume condition entry screen  1100  includes an area  1101  for entering the name of the server to which the volume is to be allocated, an area  1102  for entering the necessary capacity of the volume to be allocated, an area  1103  for entering the IOPS of the storage device required when the server utilizes the volume, an area  1104  for entering the bandwidth of the network required when the server utilizes the volume, a search button  1105  for instructing to start a search for a storage device for allocating the volume based on the conditions of areas  1101  through  1104 , and a cancel button  1106  for canceling the entry of conditions. The administrator of SAN 3  enters conditions of areas  1101  through  1104  on the volume condition entry screen  1100 , and selects the search button  1105  to advance to step  602 . In step  602 , the storage device that fulfills the conditions entered on the volume condition entry screen  1100  is searched.  
         [0053]     Next in step  603 , whether there exists a storage device that fulfills the necessary capacity and IOPS entered on the volume condition entry screen  1100  is determined based on the result of the search conducted in step  602 , and if there is no existing storage device, the procedure advances to step  604  where a screen  1200  for confirming whether to reenter conditions and search again for a storage device or to end the process is displayed.  FIG. 13  shows an example of the confirmation screen  1200 . The confirmations creen  1200  includes a message  1201  indicating that there is no storage device that fulfills the conditions, a search again button  1202  for reentering the conditions and searching for a storage device, and an end button  1203  for terminating the process. Step  605  determines the button being selected on this screen, and if search is to be executed again, that is, when the search again button  1201  is selected, the process is executed again from step  601 . If the process is to be ended, that is, when the end button  1202  is selected, the volume allocation program  13  is ended. If the candidate storage device has been successfully searched in step  603 , whether or not there is a path that fulfills the network bandwidth entered on the volume condition entry screen  1100  to connect with the storage device is determined in step  606 , and if there is a path that fulfills the conditions, the procedure advances to step  607 , and if there is no path, the procedure advances to step  613 .  
         [0054]     In step  607 , the number of candidate storage devices is determined. If there are plural storage devices as candidates, the procedure advances via step  608  to step  609 , and if there is only one candidate storage device, step  609  is carried out. In step  608 , a storage select screen  1300  is displayed for selecting one storage device out of the plural candidate storage devices.  FIG. 14  shows an example of a storage select screen  1300 . The storage select screen  1300  includes an area  1310  for indicating the list of candidate storages, and an allocation button  1305  for instructing to allocate volume to the storage device being selected in area  1310 . The area  1310  includes a storage name  1301  indicating the names of the candidate storage devices, a remaining capacity  1302  of the storage devices, an IOPS  1303  showing the remaining IOPS of the storage devices, and a remaining bandwidth  1304  of the path to the storage devices. As denoted by reference numbers  1310   a  and  1310   b , the candidate storage devices are shown. The administrator determines the storage device for allocating the volume by selecting the storage device for allocating the volume out of the candidate storage devices indicated in area  1310  and selecting the allocation button  1305 . In step  609 , a volume allocating screen  1400  is displayed, indicating that allocation is being executed.  FIG. 15  shows an example of a volume allocating screen. The volume allocating screen  1400  displays the server, the storage device and the capacity of the volume in area  1401 . Thereafter, in step  610 , a volume having the demanded capacity is created in the selected storage device, and the volume is allocated to the server. Then in step  611 , the demanded bandwidth is reserved with respect to the server to which the volume is allocated and the network equipments connecting the selected storage device, and in step  612 , a volume allocation complete screen  1500  indicating that allocation has been completed is displayed, and the process is terminated.  FIG. 16  shows an example of the volume allocation complete screen. The volume allocation complete screen  1500  displays in area  1501  the server, the storage device and the capacity of the volume for which allocation has been completed.  
         [0055]     Steps  613  through  616  correspond to the process in which there is a storage device fulfilling the entered required capacity and IOPS in the volume condition entry screen  1100  but the bandwidth of the path to the storage device does not fulfill the entered necessary bandwidth. At first, in process  613 , a bandwidth adjustment confirmation screen  1600  is displayed.  FIG. 17  shows an example of the bandwidth adjustment confirmation screen  1600 . The bandwidth adjustment confirmation screen  1600  includes an area  1610  showing the list of candidate storage devices for allocating the volume, an adjustment button  1605  for instructing execution of bandwidth adjustment between the storage device selected in area  1610  and the server, and a cancel button  1606  for instructing not to execute bandwidth adjustment. Area  1610  includes a storage name  1601  indicating the names of candidate storage devices, a remaining capacity  1602  of the storage devices, an IOPS  1603  showing the remaining IOPS of the storage devices, and a remaining bandwidth  1604  showing the remaining bandwidth of the path to the storage devices. As denoted by reference numbers  1610   a  and  1610   b , the candidate storage devices are shown. If bandwidth adjustment is to be executed, the storage device to be subjected to adjustment is selected from area  1610 , and the adjustment button  1605  is selected. If bandwidth adjustment is not to be executed, the cancel button  1606  is selected. Next in step  614 , the button being selected on the bandwidth adjustment confirmation screen  1600  is determined. If the cancel button  1606  has been selected, the process is ended. If the adjustment button is selected, in step  615 , the path management record between the storage device being selected in the bandwidth adjustment confirmation screen  1600  and the server for allocating the volume is selected from the path information  400 , and in step  616 , the bandwidth adjustment process is executed. Thereafter, the procedure advances to step  609 .  
         [0056]     Next with reference to  FIG. 8 , the details of the storage search process of step  602  are described.  FIG. 8  shows an example of a process flow related to searching for a storage device that fulfills the entered conditions. First in step  701 , the server management record of the server for allocating the volume is selected from the server management information  200  and acquired. Next in step  702 , the storage device capable of ensuring the required volume capacity and IOPS is selected based on the values of remaining capacity  103  and remaining IOPS  107  of the storage device management information  100 . Thereafter, whether a storage device fulfilling the conditions had been successfully selected or not in step  702  is determined, and if not, the process is ended, but if there were candidates, step  704  is carried out. In step  704 , a path record between the server and the storage device selected in step  702  for allocating the volume is selected from the path information  400  based on the contents of path information  401 , and the process is ended. At this time, only the record showing the remaining bandwidth capable of reserving the required bandwidth of the network is selected.  
         [0057]     Next with reference to  FIG. 19 , the details of the bandwidth adjustment process of step  616  are described.  FIG. 19  shows an example of a process flow for adjusting the bandwidth to be used between the server and the storage device. At first, in step  1801 , the volume management record corresponding to the path name  402  of the path management information  400  ( FIG. 5 ) selected in step  615  and the path name  501  of the volume allocation information  500  ( FIG. 6 ) is selected. Next in step  1802 , a bandwidth adjustment screen  1700  is displayed.  FIG. 18  shows an example of a bandwidth adjustment screen  1700 . The bandwidth adjustment screen includes an area  1710  for displaying the information on the volume management record acquired in step  1810 , a remaining bandwidth display area  1705  indicating the remaining bandwidth between the server and storage device, a requested bandwidth display area  1706  indicating the necessary capacity  1102  entered through the volume condition entry screen  1100 , and an adjustment button  1707 . The volume management record display area  1710  includes a volume  1701  for displaying the contents of the volume identifier  502  of the volume management record, a use bandwidth  1702  showing the bandwidth reserved for use of the volume shown in volume  1701 , in other words, the bandwidth  503  of the volume management record, and an adjusted bandwidth  1703  for entering the bandwidth after adjustment. In area  1710 , the data of the volume management record selected in step  1801  are listed as denoted by reference numbers  1710   a  and  1710   b . The remaining bandwidth is calculated based on the values entered in each adjusted bandwidth  1703 , and the value shown in remaining bandwidth  1705  is changed to the calculated remaining bandwidth. Thereafter, when the adjustment button  1707  is selected, the procedure advances to step  1803  of  FIG. 19 . In step  1803 , the network configuration process of  FIG. 10  is executed in order to change the reserved bandwidth of each of the volumes being changed in the bandwidth adjustment screen  1700 . Next, in step  1804 , it is confirmed whether step  1803  has been performed for all the volume management records, and if not, the procedure returns to step  1803 , but if it has been completely performed, the process is ended.  
         [0058]     Next, the details of step  611  will be described with reference to  FIG. 9 .  FIG. 9  is an example of a process flow for generating a volume in a storage device and designating the volume to be allocated to the server. First, in step  801 , a volume generation command  1000  for generating a volume to the storage device is generated.  FIG. 11 ( a ) shows one example of the layout of the volume generation command  1000 . The volume generation command  1000  discloses the contents of the transmission data, and is composed of a volume generation  1001  showing that it is a command for generating volume, and a capacity  1002  designated as the capacity of the volume being generated. Next in step  802 , the storage device in which volume is generated is connected via the management network  2 , and in step  803 , the volume generation command  1000  is transmitted. Next in step  804 , a volume generation response  1010  which is a response indicating the result of execution of the volume generation command  1000  is received from the storage device. The volume generation response  1010 , one example of which is shown in  FIG. 11 ( b ), is composed of a generation complete  1011  indicating the contents of the transmission data, a volume identifier  1012  for identifying the generated volume, and a capacity  1013  indicating the capacity of the generated volume. After receiving this volume generation response  1010 , a volume allocation command  1020  is generated in step  805 , and the volume allocation command  1020  is sent to the storage device in step  806 . The volume allocation command  1020 , one example of which is shown in  FIG. 11 ( c ), is composed of a volume allocation  1021  showing the volume allocation which is the content of the transmission data, a volume identifier  1022  showing the identifier of the volume to be allocated, a port  1023  showing the port to be used for communication with the server for which the volume is allocated, a Server name  1024  showing the server for which the volume is allocated, and an IOPS  1025  showing the IOPS used by the server for which the volume is allocated for utilizing this volume. After the volume allocation command  1020  is transmitted to the storage device, a volume allocation response  1030  which is a response showing the result of execution of the volume allocation command  1020  is received in step  807 , and the connection with the storage device is disconnected in step  808 . The volume allocation response  1030 , one example of which is shown in  FIG. 11 ( d ), is composed of an allocation complete  1031  showing completion of allocation which is the content of the transmission data, a volume identifier  1032  for identifying the allocated volume, a port  1033  showing the port of the storage device to be used when the server attempts to use the allocated volume, and a Server name  1034  indicating the server to which the volume is allocated. After cutting off the connection with the storage device in step  808 , the remaining capacity  103  and the capacity and IOPS of the volume for which the remaining IOPS  107  has been allocated of the storage management record of the storage device information  100  corresponding to the storage device for which the volume has been allocated are updated to the subtracted values in step  809 .  
         [0059]     Next, the details of the process of step  611  will be described with reference to  FIG. 10 .  FIG. 10  shows one example of a process flow for reserving the bandwidth with respect to the network equipments  31  through  38  constituting the SAN  3 . At first in step  901 , a network equipment  403  of the path record in the path information  400  selected in step  704  or step  615  is acquired in step  901 , and a network equipment management record of the network equipment management information  300  related to this network equipment is acquired. Next in step  902 , a bandwidth reservation command  1040  to be transmitted to the network equipment shown by the name  301  of the acquired network equipment management record is generated. The bandwidth reservation command  1040 , one example of which is shown in  FIG. 11 ( e ), is composed of a bandwidth reservation  1041  showing the reservation command of the bandwidth which is the content of the transmission data, a port  1042  showing the port of the network equipment for reserving the bandwidth, a bandwidth  1043  showing the bandwidth to be reserved, a Server name  1044  showing the server using the reserved bandwidth, and a storage  1044  showing the storage device. Next in process  903 , connection is formed to the network equipment shown by the name  301  on the acquired network equipment management record, and in step  904 , the generated bandwidth reservation command  1040  is sent to the connected network equipment. Thereafter, in step  905 , a bandwidth reservation response  1050  showing the response to the bandwidth reservation command  1040  is received from the network equipment. The bandwidth reservation response  1050 , one example of which is shown in  FIG. 11 ( f ), is composed of a reservation complete  1051  which is the content of the transmission data, a port  1052  indicating the port of the network equipment for which the bandwidth has been reserved, a bandwidth  1053  indicating the reserved bandwidth, a Server name  1054  indicating the server using the reserved bandwidth, and a storage name  1055  indicating the storage device that uses the reserved bandwidth. After receiving bandwidth reservation response  1050 , in step  906 , the connection with the network equipment is cut off, and in step  907 , the bandwidth is updated to a value subtracting the reserved bandwidth from the remaining bandwidth of the network equipment management record acquired in step  901 . Next in step  908 , whether or not bandwidth reservation has been performed for all the network equipments listed in network equipment  403  of the path record is confirmed. If bandwidth reservation is not performed for all the network equipments, the procedure returns to step  901 , and if the bandwidth reservation for all the network equipments has been completed, the procedure advances to step  909 . In step  909 , the value of the residual bandwidth contained in the path information  401  of the path management record is updated to a value subtracting the reserved bandwidth. Next in step  910 , whether the volume is a new volume or not is determined, and if it is new, a volume allocation record related to the allocated volume is generated in step  911 , which is added to the volume management record  500  and the process is ended. If it is not new, the volume management record is updated in step  912  and the process is ended.  
         [0060]     By the processes mentioned above, the procedure for selecting the storage device capable of reserving the designated capacity, the IOPS and the network bandwidth, allocating the volume to the server, and reserving the bandwidth of the network equipments is completed.  
         [0061]     As mentioned above, the volume allocation method in the storage area network management system according to the present embodiment selects candidate storage devices  41  through  45  for allocating the volume based on the remaining capacity and remaining IOPS of the storage devices  41  through  45  required by the server upon allocating a volume to the servers  21  through  24 , selects a storage device  41  through  45  that can be connected via a path having a remaining bandwidth that fulfills the network bandwidth required by the server, allocates the volume, and reserves the bandwidth used by the servers  21  through  24  and the storage devices  41  through  45  in which the volume is generated in network equipments  31  through  38  constituting the path between the servers  21  through  24  and the storage devices  41  through  45 . Therefore, the servers  21  through  24  are capable of effectively guaranteeing the bandwidth of the network required for the servers  21  through  24  to use the volumes of the storage devices  41  through  45 . Moreover, since not only the configuration of the storage devices  41  through  45  but also the configuration of the network equipments  31  through  48  can be set, the number of management steps can be cut down effectively.  
         [0062]     A management device was explained according to the above embodiment, but a computer or the like can be adopted as the management device of the present invention by using a computer software recording medium storing a computer program for enabling the computer to realize a function to store the connection structure information of the network equipment, the performance information of the path, and the performance information and capacity information of the storage device, and a function to select, based on stored information, the storage device that fulfills both the volume capacity and performance required by the information processing device and that comprises in its path network equipments capable of reserving the bandwidth of the network required for the communication with the information processing device, and to allocate the volume of that storage device to the image processing device. Further, a server or a storage device can be the management device of the present invention by providing the functions of the management device to the server or storage device.