Computer system, storage device and date updating method

Abstract

Computer system including: a computer with first processor managing first and second virtual computers; and a storage system with second processor providing first and second virtual volumes to the virtual computers, an original data volume shared by the virtual volumes, and a differential data volume storing first and second differential data of the virtual volumes; wherein if receiving a first request to update a first data stored in a first virtual area of the first virtual volume, the first processor requests storage of the first data in a first area of the original data volume, corresponding to the first virtual area, wherein if receiving a second request to update a second data stored in a second virtual area of the first virtual volume, the first processor requests storage of the second data in a second area of the differential data volume, corresponding to the second virtual area.

What is claimed is: 
     
         1 . A computer system comprising:
 a computer including a first processor manages a first virtual computer and a second virtual computer; and   a storage system including a second processor provides a first virtual volume to the first virtual computer and a second virtual volume to the second virtual computer, an original data volume which stores an original data shared by the first virtual volume and the second virtual volume, and a differential data volume which stores a first differential data of the first virtual volume and a second differential data of the second virtual volume;   wherein if the first processor receives a first request to update a first data stored in a first virtual area of the first virtual volume, the first processor requests the storage system to store the first data in a first area of the original data volume, the first area corresponding to the first virtual area,   wherein if the first processor receives a second request to update a second data stored in a second virtual area of the first virtual volume, the first processor requests the storage system to store the second data in a second area of the differential data volume, the second area corresponding to the second virtual area.   
     
     
         2 . A computer system according to  claim 1 ,
 wherein if the first processor receives a third request to update a third data stored in a third virtual area of the second virtual volume, the first processor requests the storage system to store the third data in the third area of the original data volume, the third area corresponding to the third virtual area,   wherein if the first processor receives a forth request to update a forth data stored in a forth virtual area of the second virtual volume, the first processor requests the storage system to store the forth data in a forth area of the differential data volume, the forth area corresponding to the forth virtual area.   
     
     
         3 . A computer system according to  claim 1 , wherein the first data is data corresponding to operating system shared by the first virtual computer and the second virtual computer. 
     
     
         4 . A computer system according to  claim 3 , wherein the second data is log data of the first virtual computer. 
     
     
         5 . A computer system according to  claim 1 ,
 wherein the computer further includes a first memory storing a management information that manages a storing flag that sets the original data volume or the differential data volume as an update data destination.   
     
     
         6 . A computer system according to  claim 4 ,
 wherein if the first processor receives the first request to update the first data stored in the first virtual area of the first virtual volume, the first processor sets the storing flag to the original data volume and requests the storage system to store the first data in the first area of the original data volume, the first area corresponding to the first virtual area,   wherein if the first processor receives the second request to update the second data stored in the second virtual area of the first virtual volume, the first processor sets the storing flag to the differential data volume and requests the storage system to store the second data in a second area of the differential data volume, the second area corresponding to the second virtual area.   
     
     
         7 . A computer system according to  claim 1 ,
 wherein the computer further includes a first memory storing a storage area management information that manages to provide the first virtual volume and the second virtual volume by using the original data volume and the differential data volume,   wherein the first processor receives a read request to read data from a third virtual area of the first virtual volume, the first processor decide whether the third virtual area is corresponding to a third area of the original data volume or a forth area of the differential data volume by referring the storage area management information, reads the data from the third area of the original data volume in case that the third virtual area is corresponding to the third area, and reads the data from the forth area of the differential data volume in case that the third virtual area is corresponding to the forth area.   
     
     
         8 . A method implemented via a computer system including:
 a computer including a first processor manages a first virtual computer and a second virtual computer; and   a storage system including a second processor provides a first virtual volume to the first virtual computer and a second virtual volume to the second virtual computer, an original data volume which stores an original data shared by the first virtual volume and the second virtual volume, and a differential data volume which stores a first differential data of the first virtual volume and a second differential data of the second virtual volume;   the method implementing operations of:   wherein if the first processor receives a first request to update a first data stored in a first virtual area of the first virtual volume, the first processor requests the storage system to store the first data in a first area of the original data volume, the first area corresponding to the first virtual area,   wherein if the first processor receives a second request to update a second data stored in a second virtual area of the first virtual volume, the first processor requests the storage system to store the second data in a second area of the differential data volume, the second area corresponding to the second virtual area.   
     
     
         9 . A method according to  claim 8 ,
 wherein if the first processor receives a third request to update a third data stored in a third virtual area of the second virtual volume, the first processor requests the storage system to store the third data in the third area of the original data volume, the third area corresponding to the third virtual area,   wherein if the first processor receives a forth request to update a forth data stored in a forth virtual area of the second virtual volume, the first processor requests the storage system to store the forth data in a forth area of the differential data volume, the forth area corresponding to the forth virtual area.   
     
     
         10 . A method according to  claim 8 , wherein the first data is data corresponding to operating system shared by the first virtual computer and the second virtual computer. 
     
     
         11 . A method according to  claim 10 , wherein the second data is log data of the first virtual computer. 
     
     
         12 . A method according to  claim 8 ,
 wherein the computer further includes a first memory storing a management information that manages a storing flag that sets the original data volume or the differential data volume as an update data destination.   
     
     
         13 . A method according to  claim 11 ,
 wherein if the first processor receives the first request to update the first data stored in the first virtual area of the first virtual volume, the first processor sets the storing flag to the original data volume and requests the storage system to store the first data in the first area of the original data volume, the first area corresponding to the first virtual area,   wherein if the first processor receives the second request to update the second data stored in the second virtual area of the first virtual volume, the first processor sets the storing flag to the differential data volume and requests the storage system to store the second data in a second area of the differential data volume, the second area corresponding to the second virtual area.   
     
     
         14 . A method according to  claim 8 ,
 wherein the computer further includes a first memory storing a storage area management information that manages to provide the first virtual volume and the second virtual volume by using the original data volume and the differential data volume,   wherein the first processor receives a read request to read data from a third virtual area of the first virtual volume, the first processor decide whether the third virtual area is corresponding to a third area of the original data volume or a forth area of the differential data volume by referring the storage area management information, reads the data from the third area of the original data volume in case that the third virtual area is corresponding to the third area, and reads the data from the forth area of the differential data volume in case that the third virtual area is corresponding to the forth area.