Abstract:
To suppress consumption of a differential volume by using a differential snapshot and a volume snapshot in combination. A program for managing a storage system including an application server that provides an application composed of a plurality of programs, a plurality of first volumes that store data that the programs use, and a plurality of second volumes set in pair states where replicas of the plurality of first volumes are stored, in which the program controls a computer to execute the procedures of: identifying any one of the plurality of programs; identifying a first volume that the identified program uses (S 11 ); extracting every second volume set in a pair state with the first volume (S 14  to S 17 ); and totalizing the first volume and the extracted second volume for the identified program (S 18 ).

Description:
CROSS-REFERENCE TO PRIOR APPLICATION  
       [0001]     This application relates to and claims priority from Japanese Patent Application No. 2004-323902, filed on Nov. 8, 2004 the entire disclosure of which is incorporated herein by reference.  
       BACKGROUND  
       [0002]     This invention relates to a storage system that replicates application data between plural volumes.  
         [0003]     In the field of SANs (Storage Area Networks) or NASs (Network Attached Storages) where integrated storages are accessed from plural servers through networks, large-scaling and high-functionalizing are underway.  
         [0004]     As an example of the high-functionalizing, a technique is known with which data of applications running on servers are replicated (copied) to remote places or the like using a remote copy function possessed by storages while continuing tasks, thereby enhancing redundancy.  
         [0005]     Also, in such a SAN or NAS, plural servers utilize plural storages, so there is a tendency that a storage system including the storages and a network will be large-scaled and complicated. In order to make use of the storages with efficiency, a technique disclosed in JP 2004-133897 A is, for instance, known with which a fault occurred to the storage or the network for connecting the storages and the servers to each other is detected without delay.  
         [0006]     In this conventional example, an event message from a device constituting the storage system is obtained and the fault is informed to a management console according to the importance of the event message.  
         [0007]     In the conventional example described above, however, there is a problem that although it is possible to identify the location at which the fault has occurred, in other words, the device to which the fault has occurred, it is impossible to know how replication by the remote copy function has been influenced by the fault.  
         [0008]     In other words, it is sufficient that an administrator administering the storage system (hereinafter referred to as the “storage administrator”) identifies to which device the fault has occurred and makes a repair to the device. On the other hand, an administrator administering tasks (applications) on the servers (hereinafter referred to as the “application administrator”) is required to grasp how the replication performed in units of the applications has been influenced by the fault occurred in the storage system and to maintain the consistency of data.  
         [0009]     However, when a fault relating to replication has occurred in a large-scaled storage system, even when the application administrator knows the location of the fault, it is extremely difficult for him/her to check how the replication relation of a volume of a storage that a specific application uses and each volume that is a replication destination of the volume has been influenced. Also, in an environment where replication is performed as to plural applications, there is also a case where the same volume is used by two or more applications. In such a case, there occurs a problem that it is extremely difficult for the application administrator to grasp the influence range of the fault occurred in the storage system with respect to the replication relation.  
       SUMMARY  
       [0010]     It is therefore an object of this invention to allow an application administrator to grasp a fault concerning replication performed in units of applications with ease and without delay.  
         [0011]     To achieve the above-mentioned objects, this invention provides a method of managing a storage system including an application server that provides an application composed of a plurality of programs, a plurality of first volumes that store data that the programs use, and a plurality of second volumes set in pair states where replicas of the plurality of first -volumes are stored, the method including: identifying any one of the plurality of programs; identifying a first volume that the identified program uses; extracting every second volume set in a pair state with the first volume; and totalizing the first volume and the second volume for the identified program.  
         [0012]     According to an aspect of this invention, operation information of the first volume and the second volume is collected, one of a fault and a faulty state of the pair state is detected as a connection state based on the operation information, and the first volume and the second volume set in the pair state and the connection state for the identified program are summarized for the totalization.  
         [0013]     Accordingly, with this invention, it becomes possible for the application administrator to monitor a volume that a specific program uses and the pair state (replication relation) of every volume set in a pair state from this volume and to monitor whether a problem has occurred to replication of data.  
         [0014]     Also, it becomes possible for the application administrator to confirm whether an abnormality has occurred to data of an application that he/she manages and a pair state at a replication destination thereof by glancing at summarized information, which allows the application administrator to grasp a fault concerning replication performed in units of applications with ease and without delay. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]      FIG. 1  is an example of a block diagram showing an overall configuration of a system.  
         [0016]      FIG. 2  is an example of a block diagram showing a software configuration.  
         [0017]      FIG. 3  is an example of a block diagram showing a volume configuration and a port configuration of the storage system.  
         [0018]      FIG. 4  is an explanatory diagram showing an example of an application configuration information table.  
         [0019]      FIG. 5  is an explanatory diagram showing an example of a configuration information and operation information table of a management server.  
         [0020]      FIG. 6  is an explanatory diagram showing an example of a pair state display table containing summarized connection states.  
         [0021]      FIG. 7  is an explanatory diagram showing an example of an influence range display table in the case of excessive I/O.  
         [0022]      FIG. 8  is an explanatory diagram showing an example of an influence range display table in the case of wire snapping.  
         [0023]      FIG. 9  is an example of a block diagram showing the volume configuration and the port configuration of the storage system in the case of the excessive I/O.  
         [0024]      FIG. 10  is an example of a block diagram showing the volume configuration and the port configuration of the storage system in the case of the wire snapping.  
         [0025]      FIG. 11  is a flowchart showing an example of pair state monitoring processing.  
         [0026]      FIG. 12  is a subroutine showing an example of pair state summarizing processing performed in a step S 18  in  FIG. 11 .  
         [0027]      FIG. 13  is a flowchart showing an example of informing processing performed by a monitoring program of an application management terminal.  
         [0028]      FIG. 14  is a flowchart showing an example of replication relation influence range identifying processing performed by a storage management program of a management server.  
         [0029]      FIG. 15  is a subroutine showing an example of processing that is performed in a step S 46  in  FIG. 14  and registers data consistency in the influence range display table.  
         [0030]      FIG. 16  is a subroutine showing an example of processing that is performed in a step S 49  in  FIG. 14  and registers the IDs of volumes connected to host-side ports in the influence range display table.  
         [0031]      FIG. 17  is a subroutine showing an example of processing that is performed in a step S 52  in  FIG. 14  and registers the IDs of volumes connected to remote-side ports in the influence range display table.  
         [0032]      FIG. 18  is a subroutine showing an example of processing that is performed in a step S 50  in  FIG. 14  and registers information necessary to registered pair states in an influence range display table concerning the host-side ports.  
         [0033]      FIG. 19  is a subroutine showing an example of processing that is performed in a step S 53  in  FIG. 14  and registers information necessary to registered pair states in an influence range display table concerning the remote-side ports. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0034]     Hereinafter, an embodiment of this invention will be described with reference to the accompanying drawings.  
         [0035]      FIG. 1  is a configuration diagram of a system to which this invention has been applied. Connected to a LAN (Local Area Network)  6  are application servers  2  to  4  that execute application programs, a management server  1  that manages storages and a SAN (Storage Area Network)  7 , an application management terminal  5  that manages the application programs of the application servers  2  to  4 , and storage systems (storage subsystems)  10000  to  10003 . It should be noted that the LAN  6  is, for instance, formed by a TCP/IP network or the like. Also, the SAN  7  is, for instance, formed by FCs (Fibre Channels), with FC switches (not shown) and the like constituting the SAN  7  being also connected to the LAN  6 .  
         [0036]     The application servers  2  to  4  are connected to the storage systems  10000  to  10003  through the SAN  7  and perform reading/writing of data and the like. The management server  1  makes settings of the storage systems  10000  to  10003  and the FC switches and performs collection of operation information (performance information) through the LAN  6 . As will be described later, the application management terminal  5  inquires of the application servers  2  to  4  and the management server  1  about a replication relation as to an application designated by an application administrator or the like who administers the application servers  2  to  4 , obtains information containing consistency of the replication relation and the like from the management server  1 , and informs the application administrator of the information.  
         [0037]     In the system configuration in  FIG. 1 , the management server  1  includes a CPU  11 , a memory  12 , a LAN interface  14 , and a disk device  13 . Also, the management server  1  is connected to the LAN  6  through the LAN interface  14 . A control program (to be described later) has been loaded into the memory  12  and the CPU  11  reads and executes the control program. Through this execution, various processing to be described later is performed.  
         [0038]     The application server  2  includes a CPU  21 , a memory  22 , a SAN interface  23  connected to the SAN  7 , and a LAN interface  24 . The application server  2  accesses the storage systems  10000  to  10003  on the SAN  7  through the SAN interface  23  and performs reading/writing of data. An application program to be described later has been loaded into the memory  22  of the application server  2  and the CPU  21  reads and executes the application program. Through this execution, a task is provided to a client (not shown) on the LAN  6 .  
         [0039]     It should be noted that the application servers  3  and  4  are also configured in the same manner as the application server  2  described above. With this configuration, the application servers  3  and  4  execute predetermined application programs, perform data access to the storage systems  10000  to  10003  through the SAN  7 , and provide tasks to the client (not shown) on the LAN  6 .  
         [0040]     Meanwhile, the storage system (storage subsystem)  10000  includes a disk device  104  and a disk controller  100  that controls the disk device  104 .  
         [0041]     In  FIG. 1 , the disk controller  100  of the storage system  10000  includes a CPU, a memory, a cache, a SAN interface  101  connected to a port  102 , and a disk interface  105 . Also, the disk controller  100  is connected to a LAN interface  103 . Further, the disk controller  100  is connected to the disk device  104  and accesses volumes set in the disk device  104  through the disk interface. It should be noted that the disk device  104  includes plural disks.  
         [0042]     The port  102  is connected to the SAN  7  and exchanges data with the application servers  2  to  4 . Also, the port  102  is connected to the LAN  6  through the LAN interface  103  and performs a setting of the volumes (storage volumes) of the disk device  104 , collection of operation information, and the like according to commands from the management server  1 . It should be noted that as will be described later, the port  102  includes a host-side port for performing communication with the application servers  2  to  4  and a remote-side port for performing communication with the storage that is a replication destination.  
         [0043]     A control program has been loaded into the memory of the disk controller  100  and the CPU  101  reads and executes the control program. Through this execution, volume setting processing, remote copy (shadow image, universal replication, true copy) between volumes or between storages, processing for obtaining operation information of each volume or each port, and the like are performed according to commands from the management server  1 . It should be noted that the universal replication refers to remote copy based on transfer of journal files (history information of writing data from the application servers  2  to  4 ).  
         [0044]     The storage systems  10001  to  10003  are also configured in the same manner as the storage system  10000  described above. With this configuration, the storage systems  10001  to  10003  execute predetermined control programs and access volumes provided on disk devices  204 ,  304 , and  404  according to requests received from the application servers  2  to  4  through the SAN  7 .  
         [0045]     Also, as will be described later, replication relations are set among the volumes of the disk devices of the storage systems  10000  to  10003 .  
         [0000]     &lt;Software Configuration&gt; 
         [0046]     Next, with reference to  FIG. 2 , a software configuration of this embodiment will be described.  
         [0047]     The application programs on the application servers  2  to  4  store data in predetermined volumes of the storages. Also, as will be described later, pair volumes for creating replicas are set for the volumes. In this embodiment, relations between volumes (hereinafter referred to as the “primary volumes”), with respect to which the application servers  2  to  4  perform reading/writing, and volumes (hereinafter referred to as the “secondary volumes”), in which the contents of the primary volumes are written and replicas are created, are referred to as the “pair states (or the pair volumes)”. In addition, a case where a replica of a primary volume is created by writing the contents of its corresponding secondary volume into another volume is also included in the pair states. Also, the pair states are applicable to between volumes in the same storage as well as between volumes of different storage systems and a case where replication chaining (pair state cascading) is performed between different storage systems is also contained in the pair states.  
         [0048]     In this embodiment, the pair states between the volumes viewed from the application programs on the application servers  2  to  4  are monitored and when it is detected that an abnormality has occurred to a pair state, the abnormality is informed to the application administrator.  
         [0049]     First, in the management server  1 , a storage management program  15  that manages the storage systems  10000  to  10003  connected to the SAN  7  is running. This storage management program  15  monitors the pair states between the volumes and operation states in units of applications, detects an abnormality, and informs the application management terminal  5  of a result of the monitoring.  
         [0050]     To do so, the storage management program  15  collects configuration information (volume configuration and path configuration, for instance) of the storage systems  10000  to  10003  from the disk controllers  100  to  400  in predetermined cycles or the like, collects operation information (I/O frequency, throughput, and side file usage ratio of each volume, for instance) of the storage systems  10000  to  10003  from the disk controllers  100  to  400  in predetermined cycles or the like, and updates a configuration information and operation information table  16 . It should be noted that the storage management program  15  may have a function of setting and changing the volume configurations and the like of the storage systems  10000  to  10003  in addition to the functions described above. It should be noted that in the operation information described above, the I/O frequency is indicated by the number of I/O bytes per second or the like and the throughput is a value expressed by the data transfer speed (kilobytes per second) of each volume or the like. Also, the side file usage ratio shows a ratio of the data cache of the disk controller used for copy of each pair state. When the side file usage ratio is low, this indicates that data writing is performed smoothly at the time of copy. On the other hand, when the side file usage ratio is high, this indicates a case where the throughput of a port used for data writing has been lowered, for instance.  
         [0051]     The disk controllers  100  to  400  of the storage systems  10000  to  10003  monitored by the management server  1  includes configuration information management units  110  to  410  that manage the volume configurations and the like of the storages and operation information management units  120  to  420  that manage the operation information of the volumes. Also, the management server  1  inquires of the disk controllers  100  to  400  of the storage systems  10000  to  10003  about the configuration information and the operation information in predetermined cycles or the like and collects the information. It should be noted that the disk controllers  100  to  400  of the storage systems  10000  to  10003  may voluntarily inform the management server  1  of the configuration information and the operation information in predetermined cycles.  
         [0052]     Next, in each of the application servers  2  to  4 , application programs are running. For instance, an application APP 1  is executed in the application server  2 , an application APP 2  is executed in the application server  3 , and an application APP 3  is executed in the application server  4 . In general, there is a case where an application is composed of plural programs. In this example, a case is shown in which the application APP 1  of the application server  2  is composed of an application program APP 1 - 1 .exe and an application program APP 1 - 2 .exe and the applications APP 2  and APP 3  of the application servers  3  and  4  are respectively composed of a single application program APP 2 - 1 .exe and a single application program APP 3 - 1 .exe.  
         [0053]     In addition, in the application servers  2  to  4 , application management programs  25 ,  35 , and  45  that manage the applications APP 1  to APP 3  are running as monitoring agents of the application servers.  
         [0054]     The application management programs  25  to  45  manage a list of programs of the applications, a list of volumes of the storage systems  10000  to  10003  that the programs use, and information showing whether the volumes are shared by other programs of the same application and/or programs of other applications as configuration information tables  26 ,  36 , and  46  in the application servers.  
         [0055]     The application programs  25  to  45  inform the management server  1  of information in the configuration information tables  26 ,  36 , and  46  according to commands from the application management terminal  5 .  
         [0056]     In the application management terminal  5 , a monitoring program  55  for monitoring the pair states in units of the applications of the application servers  2  to  4  is running. This monitoring program  55  has a list (application configuration information table  550 ) of the application programs of the applications executed at the application servers  2  to  4  and, when the application administrator designates an application name, extracts application programs corresponding to the designated application name from the application table. Then, the monitoring program  55  commands the application management programs of the application servers  2  to  4  that execute the application programs to inform the management server  1  of the configuration information of the application programs.  
         [0057]     Then, the storage management program  15  of the management server  1  returns a result of reference as to the pair states to the monitoring program  55  of the application management terminal  5  in units of application names. The monitoring program  55  displays the monitoring result received from the storage management program  15  on a display equipment (not shown) of the application management terminal  5  or the like. &lt;Volume Configuration&gt;Next, with reference to  FIG. 3 , an example of the configurations and pair states of the volumes set in the storage systems  10000  to  10003  will be described.  
         [0058]     In  FIG. 3 , volumes  001 ,  010 , and  020  are set in the disk device  104  of the storage system  10000 . In a like manner, volumes  002 ,  011 , and  021  are set in the disk device  204  of the storage system  10001 , volumes  003 ,  004 , and  012  are set in the disk device  304  of the storage system  10002 , and a volume  005  is set in the disk device  404  of the storage system  10003 .  
         [0059]     Also, a port CL 1 -A is provided for the storage system  10000  as a host-side port, is connected to the volumes  001 ,  010 , and  020 , and performs communication with the application servers  2  to  4 . In addition, a port CL 1 -D is provided as a remote-side port through which the volumes  001  and  020  are connected to the storage system  10001 .  
         [0060]     Ports CL 1 -B and CL 2 -B are provided for the storage system  10001  as host-side ports, are respectively connected to the volume  002  and the volume  011 , and perform communication with the application servers  2  to  4 . In addition, a port CL 1 -E is provided as a remote-side port through which the volumes  002  and  011  are connected to the storage system  10002 .  
         [0061]     Here, a pair state is set in which the volume  001  of the storage system  10000  is set as a primary volume (primary), the volume  002  of the storage system  10001  is set as a secondary volume (secondary), and a replica of the volume  001  is created in the volume  002 . It should be noted that this pair state is set by the management server  1  in advance (the same applies to the following description).  
         [0062]     In a like manner, the volume  010  of the storage system  10000  and the volume  011  of the storage system  10001  are set in a pair state (copy relation) and the volume  020  of the storage system  10000  is set in a pair state with the volume  021  of the storage system  10001 . Here, the volume  021  does not have a host-side port, so the pair state between the volumes  020  and  021  becomes Simplex (denoted as “SMPL” in the drawing).  
         [0063]     Then, ports CL 2 -B and CL 1 -A are provided for the storage system  10002  as host-side ports, are respectively connected to the volume  003  and the volume  004 , and perform communication with the application servers  2  to  4 . In addition, a port for remote connection is provided through which the volume  012  is connected to the storage system  10001 .  
         [0064]     Here, the volumes  003  and  004  of the storage system  10002  are set in a pair state (local copy) where the volume  003  is the primary volume thereof.  
         [0065]     Also, pair state cascading is set in which the volume  002  of the storage system  10001  is set as the primary volume (primary) of a pair state, the volume  003  of the storage system  10002  is set as the secondary volume (secondary) of the pair state, a replica of the volume  002  is created in the volume  003 , and a replica of the volume  003  is further created in the volume  004 .  
         [0066]     Also, the volume  011  of the storage system  10001  and the volume  012  of the storage system  10002  are set in a pair state.  
         [0067]     Finally, the volume  005  of the storage system  10003  is connected to the storage system  10002  through a port for remote connection and the volume  004  and the volume  005  are set in a pair state.  
         [0068]     In other words, data in the volume  001  is replicated to the volumes  002 ,  003 ,  004 , and  005  through the cascading of the pair states of the volumes. Also, the volume  020  is set in a simple pair state where a replica of data therein is created only in the volume  021 . Further, data in the volume  010  is replicated to the volumes  011  and  012  in succession through the pair state cascading.  
         [0069]     Next, with reference to  FIG. 4 , relations between the application servers  2  to  4  and the volumes of the storage systems  10000  to  10003  will be described.  FIG. 4  shows an example of the application configuration information table  550 . It should be noted that this application configuration information table  550  is set in advance by the application administrator or the like from the application management terminal  5 .  
         [0070]     In this example, the program APP 1 - 1 .exe of the application APP 1  and the program APP 3 - 1 .exe of the application APP 3  use the volume  001  of the storage system  10000 , the program APP 1 - 2 .exe of the application APP 1  uses the volume  020  of the storage system  10000 , and the program APP 2 - 1 .exe of the application APP 2  uses the volume  010  of the storage system  10000 .  
         [0000]     &lt;Outline&gt; 
         [0071]     Next, the outline of processing that is performed by the monitoring program  55  of the application management terminal  5 , the application management programs  25  to  45  of the application servers  2  to  4 , and the management server  1  and monitors the pair states of the volumes viewed from the applications will be described.  
         [0072]     First, as indicated by an arrow S 1  in  FIG. 2 , the management server  1  collects the configuration information and the operation information from the disk controllers of the storage systems  10000  to  10003  in advance or periodically and stores the collected information in the configuration information and operation information table  16  of the management server  1 . The configuration information in the configuration information and operation information table  16  shows the chaining of the pair relations of the volumes (configuration of the cascading), the relations of the allocated ports, and the like. Also, the operation information in the configuration information and operation information table  16  shows the pair states, the directions of copy, the I/O frequencies, the side file usage ratios, the throughputs between the ports, and the like.  
         [0073]      FIG. 5  shows an example of this configuration information and operation information table  16 . In  FIG. 5 , the configuration information and operation information table  16  is composed of a primary column  1611  that stores the identifiers of the primary volumes and the identifiers of the storages (storage subsystems) having the primary volumes, a secondary column  1612  that stores the identifiers of the secondary volumes and the identifiers of the storages having the secondary volumes, a host-side port ID column  1613  that stores the identifiers of the host-side ports of the volumes given in the primary column  1611 , and a remote-side port ID column  1614  that stores the identifiers of the remote-side ports of the volumes given in the primary column  1611 .  
         [0074]     Also, the configuration information and operation information table  16  includes a connection state column  1615  that stores the connection states between the primary volumes in the primary column  1611  and the secondary volumes in the secondary column  1612 . For instance, the connection states are each set to one of “COPY” indicating a state where replication (shadow image) is normal, “ERROR” indicating a case where a problem (fault) has occurred to replication, “SMPL” indicating a state where Simplex described above is normal, “WARN” indicating a case where there is a danger that a problem (fault) would occur to replication, and “PAIR” indicating a state where replication (universal replication) is normal.  
         [0075]     Further, the configuration information and operation information table  16  includes an I/O frequency column  1616  that shows the I/O transfer amounts per unit time of the host-side ports of the primary volumes, a throughput column  1617  that shows data transfer speeds per unit time between the primary volumes and the secondary volumes, and a side file usage ratio column  1618  that shows the usage ratios of the caches used for replication of the pair states. It should be noted that the I/O frequency column  1616  and the throughput column  1617  may store operation information of the host-side ports as well as the remote-side ports.  
         [0076]     Next, as indicated by an arrow S 2  in  FIG. 2 , the application administrator inputs the name of an application that is a monitoring target from the application terminal  5 . Here, a task name or an application program name may be inputted instead.  
         [0077]     In the application management terminal  5 , the application configuration information table  550  is set in advance. This application configuration information table  550  is composed of an application name column  551  that stores the names of the applications, a program name column  552  that stores the identifiers of programs of the applications whose names are given in the application name column  551 , a volume ID column  553  that stores the identifiers of the volumes of the storages that are used by the programs whose IDs are given in the program name column  552 , a shared application name column  554  that stores the names of other applications that also use the volumes whose IDs are given in the volume ID column  553 , an informing level column  555  that stores levels at which notifications (warnings) should be issued by e-mail for the states of volumes in pair states with the volumes whose IDs are given in the volume ID column  553 , a destination column  556  that stores e-mail addresses to which the notifications should be sent, and a server name column  557  that gives the identifiers of the application servers that execute the applications whose names are given in the application name column  551 .  
         [0078]     When the input described above is the input of an application program name, as indicated by an arrow S 3  in  FIG. 2 , the monitoring program  55  refers to the application configuration information table  550  shown in  FIG. 4  and instructs the application management program of the application server corresponding to the inputted program name to monitor a program having the inputted program name. Also, when the input described above is the input of an application name, the monitoring program  55  refers to the application configuration information table  550 , extracts each program name corresponding to the inputted application name from the program name column  552 , and instructs the application management program of the application server that executes each program having the extracted program name to monitor the program.  
         [0079]     As indicated by an arrow S 4  in  FIG. 2 , in the application server, the application management program refers to the configuration information table using the application name or program name inputted from the application management terminal  5  as a key and obtains information of each volume and the like corresponding to the application name or program name.  
         [0080]     Here, each of the configuration information tables  26  to  46  is a table composed of the application name column  551 , the program name column  552 , the volume ID column  553 , and the share application name column  554  among the columns of the application configuration information table  550  shown in  FIG. 4  described above, and gives information of the application executed in the application server having the configuration information table.  
         [0081]     Then, as indicated by an arrow S 5  in  FIG. 2 , the application management programs  25  to  45  sends, to the management server  1 , information of the application, in other words, a list of volumes that programs of the application uses and information showing whether the volumes are shared by other programs of the application or programs of other applications.  
         [0082]     Following this, as indicated by an arrow S 6  in  FIG. 2 , the storage management program  15  of the management server  1  refers to the configuration information and operation information table  16  using the volume list received from the application server as a key and reads the pair state (pair volume) configuration information and operation state of each volume on the volume list from the configuration information and operation information table  16 .  
         [0083]     Then, as indicated by an arrow S 7  in  FIG. 2 , the management server  1  totalizes the pair states of the volumes in units of program names using the read pair state configuration information and operation information, in other words, using a list of programs corresponding to the designated application name, a list of volumes that the programs use, information showing whether the volumes are shared by other programs of the same application or programs of other applications, the pair information of each volume on the volume list, the configuration information of cascaded volumes, and the operation states of the cascaded volumes, generates a pair state display table  17  shown in  FIG. 6  that shows the summarized connection states of the pair states, and sends the generated pair state display table  17  to the application management terminal  5 . It should be noted that  FIG. 6  relates to a case where APP 1  was inputted as the application name at the application management terminal  5 .  
         [0084]     The pair state display table  17  shown in  FIG. 6  is composed of an application name column  561  that stores the names of applications, a program name column  562  that stores the identifiers of programs constituting the applications whose names are given in the application name column  561 , a pair name column  563  that stores the paired identifiers of volumes in pair states that the programs use, a connection state column  564  that stores the connection states of the pairs, and a connection state (summary) column  565  where the connection states of the pairs have been summarized in units of program names.  
         [0085]     The connection state (summary) column  565  of this pair state display table  17  is a result of extraction of the worst connection state from among the connection states corresponding to each application name in the application name column  561 . Here, for instance, “ERROR” indicates the worst state, “WARN” indicates the next worst state, and each value other than “ERROR” and “WARN” indicates a normal state. In the case of the program APP 1 - 1 .exe of the application APP 1  in  FIG. 6 , for instance, the pair name “002-003” corresponds to the connection state “ERROR”, so the monitoring program  55  regards this connection state as a representative pair state of the program APP 1 - 1 .exe and stores “ERROR” in the connection state (summary) column  565  for this program.  
         [0086]     Then, as indicated by the arrow S 7  in  FIG. 2 , the storage management program  15  of the management server  1  transmits information in the pair state display table  17  edited in the manner described above to the application management terminal  5 . On receiving this information, as indicated by an arrow S 8  in  FIG. 2 , the monitoring program  55  of the application management terminal  5  displays the pair state display table  17  on the display equipment (not shown) and informs the application administrator or the like of the pair states summarized in units of applications.  
         [0087]     On receiving the pair state display table  17 , the monitoring program  55  of the application management terminal  5  compares the connection states in the connection state column  564  of the pair state display table  17  with the informing levels in the informing level column  555  of the application configuration information table  550 . When any connection state in the column  564  is worse than its corresponding informing level set in the informing level column  555 , the monitoring program  55  transmits an e-mail containing a corresponding application name, pair state, and connection state to a predetermined e-mail destination column  556 , thereby informing the application administrator of a warning or an abnormality.  
         [0088]     In addition, when WARN or ERROR exists in the connection state column  564  of the pair state display table  17 , the management server  1  identifies the range of an influence on application replication in the manner described below.  
         [0089]     The replication relation influence range identifying is a function of, when an abnormality has occurred to a pair volume state relating to an application that is a monitoring target or an abnormality is likely to occur thereto, selectively displaying a range where the application administrator needs to take measures and a range where the problem is considered to exert influences. When doing so, the storage management program  15  obtains operation information relating to the phenomenon that has occurred and narrows down the influence range according to the obtained operation information. Consequently, even when there have occurred phenomena that seem to be the same, the range of the narrowing down varies depending on circumstances at that time.  
         [0090]     Hereinafter, two examples of the influence range identifying by the storage management program  15  will be described. It should be noted that the details of the processing for narrowing down the influence range will be described later.  
         [0000]     1. Case of Excessive I/O  
         [0091]     First, a case where an abnormality has occurred to a pair state due to excessive disk I/O of an application will be described.  
         [0092]     When the “application APP2” is set as a monitoring target in the application management programs  25  to  45 , at a point in time when the storage management program  15  detects that the pair state of the pair “010-011” becomes “WARN” in  FIG. 5 , the storage management program  15  starts additional information obtainment for performing the narrowing down of display information.  
         [0093]     As a reason why the pair state becomes “WARN”, broadly, a possibility that “any problem has occurred to connection for pair linkage” and a possibility that “a delay has occurred to copy processing (replication) due to excessive writing into the primary volume of a pair” are conceivable. Therefore, the storage management program  15  obtains statistical information of the I/O frequency in the I/O frequency column  1616  and the throughput in the throughput column  1617  in  FIG. 5  described above and checks whether a steep change has occurred to these values. In this example, when it is found from the statistical information that the I/O frequency has significantly increased recently, the storage management program  15  extracts the volumes  001  and  020  belonging to the port CL 1 -A that the volume  010  uses for host connection from the configuration information and operation information table  16  in  FIG. 5  and judges that these volumes are appropriate as a “range in which it is required to take measures”. In other words, a state shown in  FIG. 9  has occurred in this example.  
         [0094]     Then, necessary information is stored in an influence range display table (warning display table)  18  shown in  FIG. 7  and information in this influence range display table  18  is sent to the application management terminal  5 . The monitoring program  55  of the application management terminal  5  receives the influence range display table  18  and outputs it to the display equipment.  
         [0095]     As shown in  FIG. 7 , the influence range display table  18  is composed of a primary column  1801  that stores the identifiers of primary volumes and the identifiers of storage systems (storage subsystems) having the volumes, a secondary column  1802  that stores the identifiers of secondary volumes and the identifiers of storages having the volumes, a related application name column  1803  that stores the names of applications that perform access to the volumes whose IDs are given in the primary column  1801 , a host-side port ID column  1804  that stores the identifiers of the host-side ports of the volumes whose IDs are given in the primary column  1801 , an I/O frequency column  1805  that stores the I/O frequencies of the host-side ports whose IDs are given in the host-side port ID column  1804 , a throughput column  1806  that stores the throughputs of the host-side ports whose IDs are given in the host-side port ID column  1804 , a side file usage ratio column  1807  that stores the usage ratios of caches used for replication of pair states, a data consistency (primary) column  1808  that stores the consistency of data on a primary side, and a data consistency (secondary) column  1809  that stores the consistency of data on a secondary side. It should be noted that in this example, the port IDs are used as route information between the primary volumes and a host (application server) side, although path information or the like may be used instead.  
         [0096]     It is possible for the application administrator to prevent degradation of performance of applications from occurring by performing load distribution with respect to the volume “010” that the application “APP2” uses and changing the allocated port for host connection of the volumes relating to the applications “APP1” and “APP3” with reference to the influence range display table  18  displayed on the display equipment of the application management terminal  5 . Also, in this case, no abnormality has occurred to replication itself in the pair “010-011”, so application information concerning the pair “011-012” that is cascaded with this pair volume is not contained in the influence range display table  18 .  
         [0000]     2. Case of Wire Snapping  
         [0097]     Next, a case where an abnormality has occurred to a pair state due to wire snapping of a fibre-channel cable constituting the SAN  7  will be described.  
         [0098]     When “APP1” is set as a monitoring target in the application management program  25  to  45 , at a point in time when the storage management program  15  detects that the pair state of “002-003” becomes “ERROR” in  FIG. 5 , the storage management program  15  starts additional information obtainment for performing the narrowing down of display information.  
         [0099]     As a reason why the pair state becomes “ERROR”, broadly, a possibility that “any problem has occurred to connection for pair linkage” and a possibility that “a delay has occurred to copy processing due to excessive writing into the primary volume of a pair” are conceivable.  
         [0100]     Therefore, the storage management program  15  obtains statistical information of the I/O frequency in the I/O frequency column  1616  and the throughput in the throughput column  1617  of the configuration information and operation information table  16  in  FIG. 5  and checks whether a steep change has occurred to these values. In this example, it is found from the statistical information that the throughput has become “0” from a certain point in time, so the storage management program  15  judges that the pair “011-012” belonging to the remote-side port “CL1-E” that the volume “002” uses for remote copy is appropriate as the “range in which it is required to take measures”. In other words, a state shown in  FIG. 10  has occurred in this example.  
         [0101]     Then, necessary information is stored in an influence range display table  19  in  FIG. 8  and then information in this influence range display table  19  is sent to the application management terminal  5 . The monitoring program  55  of the application management terminal  5  receives the influence range display table  19  and outputs it onto the display equipment.  
         [0102]     As shown in  FIG. 8 , the influence range display table  19  is composed of a primary column  1901  that stores the identifiers of primary volumes and the identifiers of storages (storage subsystems) having the volumes, a secondary column  1902  that stores the identifiers of secondary volumes and the identifiers of storages having the volumes, a related application name column  1903  that stores the names of applications that perform access to the volumes whose IDs are given in the primary column  1901 , a remote-side port ID column  1904  that stores the identifiers of the remote-side ports of the volumes whose IDs are given in the primary column  1901 , an I/O frequency column  1905  that stores the I/O frequencies of the remote-side ports whose IDs are given in the remote-side port ID column  1904 , a throughput column  1906  that stores the throughputs of the remote-side ports whose IDs are given in the remote-side port ID column  1904 , a side file usage ratio column  1907  that stores the usage ratios of caches that are used for replication of pair states, a data consistency (primary) column  1908  that stores the consistency of data on the primary side, and a data consistency (secondary) column  1909  that stores the consistency of data on the secondary side.  
         [0103]     It is possible for the application administrator to prevent a situation where a problem has occurred to replication from occurring by making a repair of the faulty link of the pair “002-003” that the applications “APP1” and “APP3” also use and changing the allocated port for remote copy connection of the pair “011-012” relating to the application “APP2” with reference to the information in the influence range display table  19  displayed on the application management terminal  5 . Also, in this case, replication in the pair “002-003” has ended in failure, so information showing that there is a problem in the state of the primary volume of the pair “003-004” that is cascaded with the pair “002-003” is stored in the influence range display table  19 . However, as to the pair “004-005”, its pair state is set to “SMPL”, so it is judged that no influence has been exerted on this pair and no information is stored into the influence range display table  19 .  
         [0000]     &lt;Details of Processing&gt; 
         [0104]     Next, the details of processing performed in the application management terminal  5 , the application servers  2  to  4 , and the management server  1  will be described below.  
         [0105]     First,  FIG. 11  is a flowchart showing an example of processing performed by the application management programs  25  to  45  of the application servers  2  to  4  and the storage management program  15  of the management server  1 .  
         [0106]     A step S 11  is processing performed by the application management programs  25  to  45  of the application servers  2  to  4  and steps S 12  to S 19  are processing performed by the storage management program  15  of the management server  1 .  
         [0107]     First, as indicated by the arrows S 1  and S 2  in  FIG. 2  described above, the monitoring program  55  of the application management terminal  5  receives the input of an application name by the application administrator or the like, obtains each program name and a server name corresponding to the application name from the application configuration information table  550  shown in  FIG. 4 , and transmits the obtained program name to an application server, which executes each program having the program name, as a monitoring target.  
         [0108]     Next, in the step S 11 , the application management program of the application server that received the program name from the monitoring program  55  of the application management terminal  5  obtains the volume ID of each volume that the program having the received program name uses by referring to the configuration information table and transmits the application name, the program name, and the volume ID to the management server  1 .  
         [0109]     In the step S 12 , the storage management program  15  stores the application name and the program name received from the application server in the application name column  561  and the program name column  562  of the pair state display table  17  shown in  FIG. 6 , respectively.  
         [0110]     Then, in the step S 13 , the storage management program  15  judges whether operations in the steps S 14  to S 17  have been performed for every volume that the application having the designated application name uses. When a result of this judgment is negative, the processing proceeds to the step S 14 . On the other hand, when the judgment result is positive, the processing proceeds to the step S 18 .  
         [0111]     In the step S 14 , the storage management program  15  obtains a secondary volume by searching the configuration information and operation information table  16  shown in  FIG. 5  using the received volume ID as a key, determines a pair name from the volume IDs in the primary column  1611  and the secondary column  1612 , obtains the connection state between the primary volume and the secondary volume from the connection state column  1615 , and stores the pair name and the connection state in the pair name column  563  and the connection state column  564  of the pair state display table  17 , respectively.  
         [0112]     Next, in the step S 15 , the storage management program  15  judges the presence or absence of a cascade configuration corresponding to the pair volume with reference to the presence or absence of information in the remote-side port ID column  1614  of the configuration information and operation information table  16  in  FIG. 5 . When a port ID is stored in the remote-side port ID column  1614 , the storage management program  15  judges that a cascade configuration exists and the processing proceeds to the step S 16 . On the other hand, when no port ID is stored in the remote-side port ID column  1614 , the storage management program  15  judges that no cascade configuration exists and the processing returns to the step S 13 .  
         [0113]     In the step S 16 , the storage management program  15  searches the primary column  1611  and selects pair information where the volume ID in the secondary column  1612  is set as a primary volume.  
         [0114]     In the step S 17 , as to the selected pair information, the storage management program  15  determines a pair name, obtains a pair state, and stores them in the pair state display table  17  in the same manner as in the step S 14  described above. Following this, the processing returns to the step S 15  and the operations in the steps S 15  to S 17  are repeated until the end point of the cascade configuration is reached. When the end point of the cascade configuration is reached, the processing returns to the step S 13 .  
         [0115]     When the search of the configuration information and operation information table  16  has been performed for every volume ID corresponding to the program name designated from the application server, the processing proceeds to the step S 18  in which the storage management program  15  makes a setting of the connection state (summary) column  565  of the pair state display table  17 .  
         [0116]     Following this, the storage management program  15  transmits information in the pair state display table  17  to the application management terminal  5  and ends the processing. Then, as described above, the monitoring program  55  of the application management terminal  5  outputs the received pair state display table  17  to the display equipment of the application management terminal  5 .  
         [0117]     It is possible for the application administrator to immediately know a pair state, for which it is required to take measures, as to the designated application name merely by viewing the connection state (summary) column  565  of the pair state display table  17  at the application management terminal  5 . In other words, it is possible for the application administrator to immediately grasp a pair state, for which measures should be taken, by searching for an application name, whose summarized connection state in the connection state (summary) column  565  of the pair state display table  17  is set to ERROR or WARN, and searching for a pair name, whose connection state in the connection state column  564  is set to ERROR or WARN, in the pair name column  563  corresponding to the application name whose summarized connection state is set to ERROR or WARN.  
         [0118]     Accordingly, even when replication of data corresponding to one application name is performed many times or replication is performed using a cascade configuration, it becomes possible for the application administrator to immediately grasp a pair state to which an abnormality or a warning situation has occurred, to take measures without delay, and to circumvent a loss of replication or perform recovery from a loss without delay.  
         [0119]     Next, with reference to a subroutine shown in  FIG. 12 , the pair state summarizing processing performed in the step S 18  in  FIG. 11  described above will be described in detail.  
         [0120]     In a step S 20 , the storage management program  15  obtains a list of connection states (pair states) of pairs corresponding to the program name in the pair state display table  17 .  
         [0121]     In a step S 21 , the storage management program  15  judges whether “ERROR” exists in the obtained connection state list. When a result of this judgment is positive, the processing proceeds to a step S 24  in which the storage management program  15  sets “ERROR” in the pair state (summary) column  565  and ends the subroutine.  
         [0122]     On the other hand, when the judgment result is negative, the processing proceeds to a step S 22  in which the storage management program  15  judges whether “WARN” exists in the connection state list. When a result of this judgment is positive, the processing proceeds to a step S 25  in which the storage management program  15  sets “WARN” in the pair state (summary) column  565  and ends the subroutine.  
         [0123]     On the other hand, when the judgment result is negative, the processing proceeds to a step S 23  in which the storage management program  15  sets a value (COPY, PAIR, SMPL, NORMAL, or the like, for instance) showing that the connection state is normal in the pair state (summary) column  565  and ends the subroutine.  
         [0124]     Through the processing described above, the summarized connection state column  565  of the pair state display table  17  is completed to be transmitted to the application management terminal  5 , informing the application administrator of the presence or absence of a pair state abnormality or warning.  
         [0125]     Next, with reference to  FIG. 13 , informing processing that is executed by the monitoring program  55  of the application management terminal  5  when an abnormality has occurred to a pair state will be described.  
         [0126]     A step S 30  shows processing until the processing of the storage management program  15  of the management server  1  shown in  FIGS. 11 and 12  described above is completed and the pair state display table  17  is transmitted to the application management terminal  5 .  
         [0127]     Steps S 31  and later show processing of the monitoring program  55  of the application management terminal  5  that received the pair state display table  17  from the management server  1 . In the step S 31 , the monitoring program  55  obtains information in the pair state display table  17 .  
         [0128]     In a step S 32 , the monitoring program  55  judges whether a processing end condition has been satisfied. In more detail, the monitoring program  55  judges whether the processing has been performed for every program name in the pair state display table  17 . When a result of this judgment is negative, the processing proceeds to a step S 33 . On the other hand, when the judgment result is positive, the monitoring program  55  ends the processing.  
         [0129]     In the step S 33 , the monitoring program  55  obtains the summarized connection states corresponding to the program names from the connection state (summary) column  565  one at a time, with the summarized connection state corresponding to the first program name in the pair state display table  17  being obtained first. Next, in a step S 34 , from the informing level column  555  of the application configuration information table  550  shown in  FIG. 4 , the monitoring program  55  obtains the informing level for e-mail issuance corresponding to the program name.  
         [0130]     Then, in a step S 35 , the monitoring program  55  compares the summarized connection state obtained in the step S 33  and the informing level obtained in the step S 34  with each other. When the summarized connection state agrees with the informing level or when the summarized connection state is worse than the informing level, the processing proceeds to a step S 36  in which the monitoring program  55  obtains a corresponding e-mail destination from the e-mail destination column  556 , creates an e-mail containing the program name corresponding to ERROR or WARN, and transmits the created e-mail to the obtained e-mail destination.  
         [0131]     On the other hand, when the summarized connection state is better than the informing level, the processing returns to the step S 32  and the monitoring program  55  repeatedly performs the operations in the steps S 33  to S 36  for the next program name.  
         [0132]     By repeatedly performing the processing in  FIG. 13  for every program name in the received pair state display table  17 , when an abnormality or a warning state has occurred to replication of a volume that the application uses, having the application name designated by the application management terminal  5 , it is possible to automatically inform the application administrator or the like set in advance of the abnormality or the warning state.  
         [0133]     For instance, in the pair state display table shown in  FIG. 6 , ERROR is set for the pair volume “002-003” corresponding to the program name “APP1-1.exe” corresponding to the application name “APP1”. Meanwhile, in application configuration information table  550  in  FIG. 4 , the informing level  555  corresponding to the program name “APP1-1.exe” is set to ERROR. In other words, in the case of “APP1-1.exe”, the summarized connection state and the informing level agree with each other. Consequently, the monitoring program  55  transmits the mail described above to “aaa@x.co.jp” that is the e-mail destination set in advance, thereby automatically informing the application administrator or the like of an abnormality or a state where an abnormality may occur.  
         [0134]     Next, with reference to a flowchart shown in  FIG. 14 , an example of the replication relation influence range identifying processing that is performed by the storage management program  15  of the management server  1  will be described.  
         [0135]     A step S 40  shows processing until the processing of the storage management program  15  of the management server  1  shown in  FIGS. 11 and 12  described above is completed and the pair state display table  17  is transmitted to the application management terminal  5 . Following this, in steps S 41  and later, the replication relation influence range identifying processing is performed.  
         [0136]     In the step S 41 , the storage management program  15  judges whether a processing end condition has been satisfied. In more detail, the storage management program  15  judges whether the processing has been performed for every program name in the pair state display table  17 . When a result of this judgment is negative, the processing proceeds to a step S 42 . On the other hand, when the judgment result is positive, the storage management program  15  ends the processing.  
         [0137]     In the step S 42 , the storage management program  15  obtains the summarized connection states corresponding to the program names from the connection state (summary) column  565  one at a time, with the summarized connection state corresponding to the first program name in the pair state display table  17  being obtained first.  
         [0138]     In a step S 43 , the storage management program  15  judges whether the obtained summarized connection state is “WARN”. When a result of this judgment is positive, the processing proceeds to a step S 44 . On the other hand, when the judgment result is negative, the processing proceeds to a step S 45 . In the step S 44 , the storage management program  15  refers to the configuration information and operation information table  16  in  FIG. 5  using the volume IDs corresponding to the program name in the pair state display table  17  as a key, obtains volume IDs and subsystem IDs from the primary column  1611  and the secondary column  1612 , stores the volume ID and subsystem ID corresponding to a primary volume and the volume ID and subsystem ID corresponding to a secondary volume in the primary column  1801  and the secondary column  1802  of the influence range display table  18  shown in  FIG. 7  respectively, and sets “no problem” showing that there exist no data loss in the data consistency (primary) column  1808  and the data consistency (secondary) column  1809 . Also, the storage management program  15  sets a corresponding application name in the related application name column  1803 .  
         [0139]     Next, in the step S 45 , the storage management program  15  judges whether the summarized connection state is “ERROR”. When a result of this judgment is positive, the processing proceeds to a step S 46 . On the other hand, when the judgment result is negative, the processing proceeds to a step S 47 . In the step S 46 , the storage management program  15  refers to the configuration information and operation information table  16  in  FIG. 5  using the volume IDs corresponding to the program name in the pair state display table  17  as a key, obtains volume IDs and subsystem IDs from the primary column  1611  and the secondary column  1612 , stores the volume ID and subsystem ID corresponding to a primary volume and the volume ID and subsystem ID corresponding to a secondary volume in the primary column  1901  and the secondary column  1902  of the influence range display table  19  shown in  FIG. 8  respectively, and sets one of “any problem” or “no problem” in the data consistency (primary) column  1908  and the data consistency (secondary) column  1909  according to the presence or absence of a data loss at a replication source or replication destination due to a wire snapping state in a manner to be described later. Also, the storage management program  15  sets a corresponding application name in the related application name column  1903 .  
         [0140]     In the step S 47 , the storage management program  15  obtains statistical information of the I/O frequency and the throughput corresponding to the primary volume for which ERROR or WARN has been set. It is sufficient that this statistical information is information with which it is possible to find steep changes of the I/O frequency and the throughput.  
         [0141]     In a step S 48 , the storage management program  15  judges whether the I/O frequency corresponding to the primary volume has increased steeply. When a result of this judgment is positive, the processing proceeds to a step S 49 . On the other hand, when the judgment result is negative, the processing proceeds to a step S 51 .  
         [0142]     In the step S 49 , the storage management program  15  obtains the volume ID of each volume connected to the host-side port of the volume corresponding to the current program name from the configuration information and operation information table  16  in  FIG. 5  and sets the obtained volume ID in the influence range display table  18 . Next, in a step S 50 , the storage management program  15  sets information that is necessary to each pair state corresponding to the current program name in the influence range display table  18 .  
         [0143]     In the step S 51 , the storage management program  15  judges whether the throughput corresponding to the primary volume has decreased steeply. When a result of this judgment is positive, the processing proceeds to a step S 52 . On the other hand, when the judgment result is negative, the processing returns to the step S 4   1 .  
         [0144]     In the step S 52 , the storage management program  15  obtains the volume ID of each volume connected to the remote-side port of the volume corresponding to the current program name from the configuration information and operation information table  16  in  FIG. 5  and sets the obtained volume ID in the influence range display table  19 . Next, in a step S 53 , the storage management program  15  sets information that is necessary to each pair state corresponding to the current program name in the influence range display table  19 . Then, the processing returns to the step S 41  and the storage management program  15  repeats the operations in the steps S 41  to S 53  described above until the processing have been performed for every program name. In this manner, the influence range display tables  18  and  19  are created. With the influence range display tables  18  and  19 , it becomes possible for the application administrator to grasp each pair volume influenced by excessive I/O or wire snapping in a replication relation with ease and without delay.  
         [0145]     Next, with reference to a subroutine shown in  FIG. 15 , an example of processing that is performed in the step S 46  in  FIG. 14  described above and registers data consistency in the influence range display table  19  will be described.  
         [0146]     In a step S 60 , the storage management program  15  refers to the pair state display table  17  in  FIG. 6  to find volume IDs in the pair name column  563 , for which “ERROR” is set in the connection state column  564 , and sets “any problem” in the data consistency (primary) column  1908  and the data consistency (secondary) column  1909  of the influence range display table  19  in  FIG. 8  for the found volume IDs.  
         [0147]     Next, in a step S 6   1 , the storage management program  15  refers to the configuration information and operation information table  16  in  FIG. 5  and, when there exists no volume cascade configuration corresponding to the current program name or when the pair state corresponding to the current program name is SMPL, ends the subroutine. On the other hand, when there exists a cascade configuration, the processing proceeds to a step S 62  in which the storage management program  15  obtains from the configuration information and operation information table  16  in  FIG. 5 , a pair state where the secondary volume of the current pair state is set as a primary volume.  
         [0148]     Then, in a step S 63 , the storage management program  15  registers the primary volume ID and the secondary volume ID of the pair state obtained in the step S 62  described above in the primary column  1901  and the secondary column  1902  of the influence range display table  19  and also registers “any problem” in the data consistency columns  1908  and  1909  of the table  19 . Then, the processing returns to the step S 61  described above and the operations in the steps S 61  to S 63  are repeated until the end point of the cascade configuration is reached.  
         [0149]     Through the processing described above, “any problem” is set in the data consistency columns for each pair volume cascaded with a pair volume, for which ERROR is set in the connection state column, because there is a high possibility that a data loss may exist in the cascaded pair volume.  
         [0150]     Next, with reference to a subroutine shown in  FIG. 16 , an example of processing that is performed in the step S 49  in  FIG. 14  described above and registers the volume ID of each volume connected to the host-side port of a pair volume, to which a problem has occurred, in the influence range display table  18  will be described.  
         [0151]     In a step S 70 , the storage management program  15  obtains the port ID of the host-side port of a pair volume, to which ERROR (or WARN) has occurred, by referring to the configuration information and operation information table  16  in  FIG. 5 .  
         [0152]     Then, in a step S 71 , the storage management program  15  judges whether a subroutine end condition has been satisfied. In more detail, the storage management program  15  judges whether the processing has been performed for every primary volume ID in the configuration information and operation information table  16 . When a result of this judgment is positive, the storage management program  15  ends this subroutine. On the other hand, when the judgment result is negative, the processing proceeds to a step S 72 .  
         [0153]     In the step S 72 , the storage management program  15  judges whether the volume ID of a current primary volume is contained in the pair name column  563  of the pair state display table  17 , with the first primary volume in the configuration information and operation information table  16  being set as the current primary volume first. When a result of this judgment is positive, the processing returns to the step S 71  and the next volume ID is set as a new check target. On the other hand, when the judgment result is negative, the processing proceeds to a step S 73 .  
         [0154]     In the step S 73 , the storage management program  15  obtains the port ID of the host-side port corresponding to the volume ID of the current primary volume from the configuration information and operation information table  16 . Next, in a step S 74 , the storage management program  15  judges whether the obtained port ID agrees with the port ID corresponding to the pair volume to which ERROR has occurred. When a result of this judgment is positive, the processing proceeds to a step S 75  in which the storage management program  15  registers the primary volume ID and its corresponding secondary volume ID in the primary and secondary columns  1801  and  1802  of the influence range display table  18  and also registers “no problem” in the data consistency columns  1808  and  1809  of the table  18 .  
         [0155]     Following this, the processing returns to the step S 71  and the port ID comparison is performed for every primary volume ID.  
         [0156]     Through the processing described above, pair volumes corresponding to the port ID of the host-side port, to which a volume where ERROR or WARN has occurred is connected, are registered in succession in the influence range display table  18 .  
         [0157]     Next, with reference to a subroutine shown in  FIG. 17 , an example of processing that is performed in the step S 52  in  FIG. 14  described above and registers the volume ID of each volume connected to the remote-side port of a pair volume, to which a problem has occurred, in the influence range display table  19  will be described.  
         [0158]     In a step S 80 , by referring to the configuration information and operation information table  16  in  FIG. 5 , the storage management program  15  obtains the port ID of the remote-side port of a pair volume, to which ERROR (or WARN) has occurred.  
         [0159]     Next, in a step S 8   1 , the storage management program  15  judges whether a subroutine end condition has been satisfied. In more detail, the storage management program  15  judges whether the processing has been performed for every primary volume ID in the configuration information and operation information table  16 . When a result of this judgment is positive, the storage management program  15  ends the subroutine. On the other hand, when the judgment result is negative, the processing proceeds to a step S 82 .  
         [0160]     In the step S 82 , the storage management program  15  judges whether the volume ID of a current primary volume is contained in the pair name column  563  of the pair state display table  17 , with the first primary volume in the configuration information and operation information table  16  being set as the current primary volume first. When a result of this judgment is positive, the processing returns to the step S 81  and the next volume ID is set as a new check target. On the other hand, when the judgment result is negative, the processing proceeds to a step S 83 .  
         [0161]     In the step S 83 , the storage management program  15  obtains the port ID of the remote-side port corresponding to the volume ID of the current primary volume from the configuration information and operation information table  16 . Next, in a step S 84 , the storage management program  15  judges whether the obtained port ID agrees with the port ID corresponding to the pair volume to which ERROR has occurred. When a result of this judgment is positive, the processing proceeds to a step S 85  in which the storage management program  15  registers the primary volume ID and its corresponding secondary volume ID in the primary and secondary columns  1901  and  1902  of the influence range display table  19  and also registers “no problem” in the data consistency columns  1908  and  1909  of the table  19 .  
         [0162]     Following this, the processing returns to the step S 81  and the port ID comparison is performed for every primary volume ID.  
         [0163]     Through the processing described above, pair volumes corresponding to the port ID of the remote-side port, to which a volume where ERROR or WARN has occurred is connected, are registered in succession in the influence range display table  19 .  
         [0164]     Next, with reference to a subroutine shown in  FIG. 18 , an example of processing that is performed in the step S 50  in  FIG. 14  described above and registers information that is necessary to registered pair states in the influence range display table  18  concerning the host-side ports will be described.  
         [0165]     In a step S 90 , the storage management program  15  judges whether a subroutine end condition has been satisfied. In more detail, the storage management program  15  judges whether the processing has been performed for every primary volume ID in the influence range display table  18 . When a result of this judgment is positive, the storage management program  15  ends the subroutine. On the other hand, when the judgment result is negative, the processing proceeds to a step S 91 .  
         [0166]     In the step S 91 , the storage management program  15  judges whether a current volume ID is contained in the pair state display table  17 , with the first primary volume ID in the influence range display table  18  being set as the current volume ID first. When a result of this judgment is positive, the processing proceeds to a step S 93 . On the other hand, when the judgment result is negative, the processing proceeds to a step S 92 .  
         [0167]     In the step S 92 , the current volume ID is not contained in the pair state display table  17 , so the storage management program  15  informs the application management programs  25 ,  35 , and  45  of the volume ID and obtains the application name corresponding to the volume ID. On the other hand, in the step S 93 , the storage management program  15  obtains the application name corresponding to the volume ID from the pair state display table  17 .  
         [0168]     Next, in a step S 94 , the storage management program  15  registers the obtained application name in the related application name column  1803  of the influence range display table  18  at a location corresponding to the volume ID.  
         [0169]     Then, in a step S 95 , the storage management program  15  obtains the port ID of the host-side port corresponding to the volume ID from the configuration information and operation information table  16  and registers the obtained port ID in the host-side port ID column  1804  of the influence range display table  18 .  
         [0170]     Next, in a step S 96 , the storage management program  15  obtains an I/O frequency corresponding to the volume ID from the configuration information and operation information table  16  and registers the obtained I/O frequency in the I/O frequency column  1805  of the influence range display table  18 . Following this, in a step S 97 , the storage management program  15  obtains a throughput corresponding to the volume ID from the configuration information and operation information table  16  and registers the obtained throughput in the throughput column  1806  of the influence range display table  18 . Then, in a step S 98 , the storage management program  15  obtains a side file usage ratio corresponding to the volume ID from the configuration information and operation information table  16  and registers the obtained side file usage ratio in the side file usage ratio column  1807  of the influence range display table  18 .  
         [0171]     By performing the operations in the steps S 90  to S 98  described above for every primary volume ID in the influence range display table  18 , the influence range display table  18  is generated.  
         [0172]     Next, with reference to a subroutine shown in  FIG. 19 , an example of processing that is performed in the step S 53  in  FIG. 14  described above and registers information that is necessary to registered pair states in the influence range display table  19  concerning the remote-side ports will be described.  
         [0173]     Like the steps S 90  to S 98  in  FIG. 18  described above, steps S 100  to S 108  in  FIG. 19  are repeatedly executed for every primary volume ID in the influence range display table  19 . Also, in the case of  FIG. 18 , the host-side port ID, I/O frequency, throughput, and side file usage ratio corresponding to the primary volume ID are obtained and are registered in the influence range display table  18  in the steps S 95  and later. In contrast to this, in the case of  FIG. 19 , the remote-side port ID, I/O frequency, throughput, and side file usage ratio corresponding to the primary volume ID are obtained and are registered in the influence range display table  19  in the steps S 105  and later. In other steps, the same operations as in the case of  FIG. 18  are performed.  
         [0174]     By performing the operations in the steps S 100  to S 108  for every primary volume ID in the influence range display table  19 , the influence range display table  19  is generated.  
         [0175]     As a result of the replication relation influence range identifying described above, when an abnormality has occurred to the state of a pair volume relating to an application that is a monitoring target or when an abnormality may occur to the state of the pair volume (when warning has occurred thereto), a range where it is necessary to take measures and a range where the problem seems to exert influences are selectively displayed. When doing so, the storage management program  15  obtains operation information relating to the phenomenon that has occurred and narrows down the influence range according to the obtained operation information. Consequently, even when there have occurred phenomena that seem to be the same, the range of the narrowing down varies depending on circumstances at that time. Therefore, it becomes possible to exhibit an appropriate influence range to the application administrator.  
         [0176]     As described above, according to this invention, it becomes possible to monitor each volume that a specific application uses and the pair state (replication relation) of each volume cascaded or paired therefrom and to monitor whether a problem has occurred to replication of data.  
         [0177]     After obtaining each program name and each volume ID corresponding to a specific application name from the application configuration information table  550  shown in  FIG. 4 , the application management terminal  5  transmits them to the management server  1 . The management server  1  obtains the pair state corresponding to the volume ID from the configuration information and operation information table shown in  FIG. 5  and stores the obtained information in the pair state display table. At this time, the management server  1  also obtains the pair state of each cascaded volume from the configuration information and operation information table and stores it in the pair state display table. Finally, the management server  1  adds information where the pair states have been summarized to the pair state display table and then provides this table to the application management terminal  5  that the application administrator uses. With the summarized information in the table, it becomes possible for the application administrator to confirm whether an abnormality has occurred to data that he/she manages and each pair state at a replication destination of the data at a glance.  
         [0178]     It should be noted that in the embodiment described above, the tracing of pair volumes (replication relation) that an application uses and the detection of a fault are performed by the storage management program  15  of the management server  1  and the monitoring program  55  of the application management terminal  5 , although the storage management program  15  and the monitoring program  55  may be executed in the same computer.  
         [0179]     Also, in the embodiment described above, the application configuration information table  550  is provided in the application management terminal  5 , although this table  550  may be provided in each of the application servers  2  to  4  and may be inquired from the application management terminal  5 .  
         [0180]     While the present invention has been described in detail and pictorially in the accompanying drawings, the present invention is not limited to such detail but covers various obvious modifications and equivalent arrangements, which fall within the purview of the appended claims.