A storage apparatus connectable to another storage apparatus so as to receive data therefrom, the storage apparatus comprising: storage units (241 to 244) configured to store data; and a controller configured to control a virtual volume utilizing the storage units (241 to 244), wherein the virtual volume is a variable allocation of storage units (241 to 244) according to a usage pattern of the virtual volume, wherein the controller is configured to allocate physical storage area in the variable allocation of storage units (241 to 244) to the virtual volume in units of blocks; the controller being operable to: determine whether data received from the other storage apparatus is real data or compressed zero data, the compressed zero data regarding an initial address and a block length of a copy target area of a copy source of a virtual volume of the other storage apparatus; determine whether a copy destination area of the virtual volume is allocated to at least one of the storage units (241 to 244); selectively allocate or not allocate the copy destination area to the storage unit (241 to 244) in accordance with a combination of the determination, and copy the real data into the copy destination area when the copy destination area is allocated, wherein, if it is determined that the data received is compressed zero data and the copy destination area would occupy an entire block of the physical storage area, the controller is configured such that the physical storage area is not allocated to the virtual volume, and wherein, if it is determined that the data received is compressed zero data and the copy destination area would occupy part of a block of the physical storage area, the controller is configured to allocate the physical storage area to the virtual volume and to copy zero data to the part of the block of the physical storage area to be occupied by the copy destination area. storage units (241 to 244) configured to store data; and a controller configured to control a virtual volume utilizing the storage units (241 to 244), wherein the virtual volume is a variable allocation of storage units (241 to 244) according to a usage pattern of the virtual volume, wherein the controller is configured to allocate physical storage area in the variable allocation of storage units (241 to 244) to the virtual volume in units of blocks; the controller being operable to: determine whether data received from the other storage apparatus is real data or compressed zero data, the compressed zero data regarding an initial address and a block length of a copy target area of a copy source of a virtual volume of the other storage apparatus; determine whether a copy destination area of the virtual volume is allocated to at least one of the storage units (241 to 244); selectively allocate or not allocate the copy destination area to the storage unit (241 to 244) in accordance with a combination of the determination, and copy the real data into the copy destination area when the copy destination area is allocated, wherein, if it is determined that the data received is compressed zero data and the copy destination area would occupy an entire block of the physical storage area, the controller is configured such that the physical storage area is not allocated to the virtual volume, and wherein, if it is determined that the data received is compressed zero data and the copy destination area would occupy part of a block of the physical storage area, the controller is configured to allocate the physical storage area to the virtual volume and to copy zero data to the part of the block of the physical storage area to be occupied by the copy destination area. determine whether data received from the other storage apparatus is real data or compressed zero data, the compressed zero data regarding an initial address and a block length of a copy target area of a copy source of a virtual volume of the other storage apparatus; determine whether a copy destination area of the virtual volume is allocated to at least one of the storage units (241 to 244); selectively allocate or not allocate the copy destination area to the storage unit (241 to 244) in accordance with a combination of the determination, and copy the real data into the copy destination area when the copy destination area is allocated, wherein, if it is determined that the data received is compressed zero data and the copy destination area would occupy an entire block of the physical storage area, the controller is configured such that the physical storage area is not allocated to the virtual volume, and wherein, if it is determined that the data received is compressed zero data and the copy destination area would occupy part of a block of the physical storage area, the controller is configured to allocate the physical storage area to the virtual volume and to copy zero data to the part of the block of the physical storage area to be occupied by the copy destination area.