Storage control device and raid group extension method
AssigneeHitachi, Ltd.
InventorsYutaka Watanabe, Keishi Tamura
Life of this patent
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Abstract
The storage system includes a first storage subsystem having a first logical volume to be accessed by a host computer, and a second storage subsystem connected to the first storage subsystem and having a second logical volume to be mapped to the first logical volume. The first storage subsystem includes a memory having definition information for defining a plurality of logical paths that transfer, to the second logical volume, I/O from the host computer to the first logical volume, and a transfer mode of the I/O to the plurality of logical paths. At least two or more logical paths among the plurality of logical paths are defined as active, and the controller transfers the I/O to the at least two or more logical paths set as active.
Claims14
A storage system, comprising:
- a first storage subsystem having a first logical volume to be accessed by a host computer;
- and
- a second storage subsystem connected to the first storage subsystem and having a second logical volume to be mapped to the first logical volume;
- wherein the first storage subsystem includes:
- a memory having definition information for defining a plurality of logical paths between the first logical volume and the second logical volume through which I/O from the host computer to the first logical volume is transferred, and a transfer mode of the I/O through the plurality of logical paths;
- and
- a controller for controlling the transfer of the I/O based on the definition information,
- wherein if the transfer mode is changed to a single path mode in which the I/O is transferred using one of the plurality of logical paths, the controller register the single path mode as the transfer mode in the definition information,
- wherein if the transfer mode is changed to a multi path mode in which the I/O is transferred using the plurality of logical paths for balancing I/O load, the controller checks whether the second storage subsystem supports the multi path mode and register the multi path mode as the transfer mode in the definition information in case that the second storage subsystem supports the multi path mode.
A control method of a storage system in which a second storage subsystem is connected, the method comprising:
- managing definition information for defining a plurality of logical paths between the first logical volume and the second logical volume through which I/O from the host computer to the first logical volume is transferred, and a transfer mode of the I/O through the plurality of logical paths;
- registering the single path mode as the transfer mode in the definition information if the transfer mode is changed to a single path mode in which the I/O is transferred using one of the plurality of logical paths;
- checking whether the second storage subsystem supports the multi path mode if the transfer mode is changed to a multi path mode in which the I/O is transferred using the plurality of logical paths for balancing I/O load;
- and
- registering the multi path mode as the transfer mode in the definition information in case that the second storage subsystem supports the multi path mode.
Dependencies are inferred from the claim text.