Method for controlling storage device controller, storage device controller, and program

A first storage controller being adapted to be used in a system including first storage controller, a second storage controller and a plurality of storage devices, the first storage controller comprising:

• at least one processing unit being adapted to start to split a plurality of pairs in the consistency group upon receiving a group split command being created for the consistency group,
• wherein the processing unit is adapted to suppress an execution of a write request, addressed to a volume in the consistency group, after receiving the group split command for splitting the pairs in the consistency group, and
• wherein the processing unit is adapted to execute a write request addressed to a volume, which is not in the consistency group, during splitting the pairs in the consistency group.

A computer program, for a first storage controller, stored on at least one computer readable storage medium and implemented in the first storage controller in a system including the first storage controller, a second storage controller and a plurality of storage devices, the computer program comprising:

• code for starting to split a plurality of pairs of paired volumes in a group upon receiving a group split command for the group;
• and
• code for suppressing an execution of a write request, addressed to a volume in the group, after receiving the group split command, until a completion of splitting the pairs of the paired volumes in the group.

A computer program, for a first storage controller, stored on at least one computer readable storage medium and implemented in the first storage controller in a system including the first storage controller, the second storage controller and a plurality of storage devices, the computer program comprising:

• code for starting to split a plurality of pairs in a consistency group based on a group split command for the consistency group;
• and
• code for executing a write request after a completion of splitting the pairs in the consistency group, the write request being addressed to a volume in the consistency group during splitting the pairs in the consistency group.

A first storage controller being adapted to be used in a system including the first storage controller, a second storage controller and a plurality of storage devices, the first storage controller comprising:

• at least one processing unit being adapted to start to split a plurality of pairs of paired volumes in a consistency group upon receiving a group split command for the consistency group;
• wherein the processing unit is adapted to execute a write request after a completion of splitting the pairs of the paired volumes in the consistency group, the write request being addressed to a volume in the consistency group during splitting the pairs of paired volumes in the consistency group.

A first storage controller being adapted to be used in a system including the first storage controller, a second storage controller and a plurality of storage devices, the first storage controller comprising:

• at least one processing unit being adapted to start to split a plurality of pairs in a consistency group upon receiving a group split command being created for the consistency group;
• wherein the processing unit is adapted to execute a write request after a completion of splitting the pairs, the write request being addressed to a volume in the consistency group during splitting the pairs in the consistency group, and
• wherein the processing unit is adapted to execute a write request addressed to a volume, which is not in the consistency group, during splitting the pairs in the consistency group.