Storage system

A storage system including a host system, a first storage apparatus having a first primary volume group and a first secondary volume group to be connected to said host system, and a second storage apparatus having a second primary volume group and a second secondary volume group, and which duplicates data by connecting said second storage apparatus to said host system and said first storage apparatus, configuring a first pair with said first primary volume and said second secondary volume group, and configuring a second pair with said second primary volume group and said first secondary volume group;

• wherein said first storage apparatus comprises:
• a first mapping table for storing first mapping information which associates first information that specifies the respective primary volumes in said first primary volume group and second information that specifies the respective secondary volumes in said second secondary volume group;
• and
• a first control unit for writing first data in a relevant primary volume upon receiving from said host system a command for writing said first data in any one of the primary volumes in said first primary volume group, and sending to said second storage apparatus a first command for writing said first data in a secondary volume corresponding to the primary volume to be written with said first data specified using said first mapping information, and for writing second data in a relevant secondary volume upon receiving from said host system a command for writing said second data in a secondary volume in said first secondary volume group, and sending to said second storage apparatus a second command for writing said second data in a primary volume corresponding to the secondary volume to be written with said second data specified using said first mapping information;
• and
• wherein said second storage apparatus comprises:
• a second mapping table for storing second mapping information associated with the same contents as said first mapping information;
• and
• a second control unit for writing third data in a relevant primary volume upon receiving from said host system a command for writing said third data in any one of the primary volumes in said second primary volume group, and sending to said first storage apparatus a third command for writing said third data in a second volume corresponding to the primary volume to be written with said third data specified using said second mapping information, and for writing fourth data in a relevant secondary volume upon receiving from said host system a command for writing said fourth data in a secondary volume in said second secondary volume group, and sending to said first storage apparatus a fourth command for writing said fourth data in a primary volume corresponding to the secondary volume to be written with said fourth data specified using said second mapping information.

A storage system including a first host system, a first storage apparatus having a first primary volume group to be connected to said first host system, a second storage apparatus having a first secondary volume group and a second secondary volume group, a second host system, and a second primary volume group to be connected to said second host system, and which duplicates respective data by connecting said second storage apparatus to said first host system, said first storage apparatus, said second host system and said third storage apparatus, configuring a pair with the first primary volume group of said first storage apparatus and said first secondary volume group, and configuring a pair with the second primary volume group of said third storage apparatus and said second secondary volume group,

• wherein said first storage apparatus comprises:
• a first mapping table for storing first mapping information which associates first information that specifies the respective primary volumes in said first primary volume group and second information that specifies the respective secondary volumes in said first secondary volume group;
• a first control unit for writing first data in a relevant primary volume upon receiving from said first host system a command for writing said first data in any one of the primary volumes in said first primary volume group, and sending to said second storage apparatus a first command for writing said first data in a secondary volume corresponding to the primary volume to be written with said first data specified using said first mapping information;
• a second mapping table for storing second mapping information which associates third information that specifies the respective primary volumes in said second primary volume group and fourth information that specifies the respective volumes in said second secondary volume group;
• and
• a second control unit for writing second data in a relevant primary volume upon receiving from said second host system a command for writing said second data in any one of the primary volumes in said second primary volume group, and sending to said second storage apparatus a second command for writing said second data in a secondary volume corresponding to the primary volume to be written with said second data specified using said second mapping information;
• wherein said second storage apparatus comprises:
• a third mapping table for storing third mapping information associated with the same contents as said first mapping information;
• a fourth mapping table for storing fourth mapping information associated with the same contents as said second mapping information;
• and
• a third control unit for writing third data in a relevant secondary volume upon receiving from said first host system a command for writing said third data in any one of the secondary volumes in said first secondary volume group, and sending to said first storage apparatus a third command for writing said third data in a primary volume corresponding to the secondary volume to be written with said third data specified using said third mapping information, and for writing fourth data in a relevant secondary volume upon receiving from said second host system a command for writing said fourth data in any one of the secondary volumes in said second secondary volume group, and sending to said third storage apparatus a fourth command for writing said fourth data in a primary volume corresponding to the secondary volume to be written with said fourth data specified using said fourth mapping information.