System and method for managing virtual hard disks in cloud environments

Abstract

A system, method, and computer-readable storage medium for managing virtual hard disks in a cloud computing/storage environment are provided. The method includes associating, using a virtual hard disk (VHD) management system of a server device, a plurality of data blocks of a virtual hard disk stored at a cloud vendor to a corresponding plurality of cloud objects. A plurality of cloud object identifiers associated with the plurality of cloud objects in a first cloud allocation table are stored. Changes to one or more data blocks are determined. Corresponding new cloud allocation tables for every data block in the plurality of data blocks that has changed are formed, the new cloud allocation tables having corresponding new cloud object identifiers. The first and the new cloud allocation tables are downloaded and merged to form an updated cloud allocation table. The updated cloud allocation table is uploaded to the cloud vendor.

What is claimed is: 
     
         1 . A method for managing virtual hard disks in a cloud computing/storage environment, comprising:
 associating, using a virtual hard disk (VHD) management system of a server device, a plurality of data blocks of a virtual hard disk stored at a cloud vendor to a corresponding plurality of cloud objects;   storing, using the VHD management system, a plurality of cloud object identifiers associated with the plurality of cloud objects in a first cloud allocation table;   determining, using the VHD management system, changes to one or more data blocks in the plurality of data blocks;   forming, using the VHD management system, corresponding new cloud allocation tables for every data block in the plurality of data blocks that has changed, the new cloud allocation tables having corresponding new cloud object identifiers;   downloading, using the VHD management system, the first and the new cloud allocation tables;   merging, at the VHD management system, the first and the new cloud allocation tables to form an updated cloud allocation table; and   uploading, using the VHD management system, the updated cloud allocation table to the cloud vendor such that the updated cloud allocation table includes information regarding the changed data blocks in the plurality of data blocks.   
     
     
         2 . The method of  claim 1 , wherein the merging comprises:
 detecting updated cloud object identifiers in the first and the new cloud allocation tables to form updated cloud object identifiers in the updated cloud allocation table.   
     
     
         3 . The method of  claim 1 , wherein the determining the changes is based upon determining which sectors of the one or more data blocks have changed. 
     
     
         4 . The method of  claim 3 , wherein the cloud object identifiers are Boolean indicators in the first and the new cloud allocation tables. 
     
     
         5 . The method of  claim 1 , wherein for each data block that is changed in the one or more data blocks, the new cloud object identifiers are created. 
     
     
         6 . The method of  claim 1 , wherein the plurality of data blocks store respective snapshots of virtual machine images. 
     
     
         7 . The method of  claim 1 , wherein the first cloud allocation and the new cloud allocation tables are smaller in size than the data blocks such that a time taken for the downloading is less than a time taken for downloading the data blocks. 
     
     
         8 . A tangible computer-readable storage medium having one or more computer-readable instructions thereon for managing virtual hard disks in a cloud computing/storage environment, which when executed by one or more processors cause the one or more processors to:
 associate, using a virtual hard disk (VHD) management system of a server device, a plurality of data blocks of a virtual hard disk stored at a cloud vendor to a corresponding plurality of cloud objects;   store, using the VHD management system, a plurality of cloud object identifiers associated with the plurality of cloud objects in a first cloud allocation table;   determine, using the VHD management system, changes to one or more data blocks in the plurality of data blocks;   form, using the VHD management system, corresponding new cloud allocation tables for every data block in the plurality of data blocks that has changed, the new cloud allocation tables having corresponding new cloud object identifiers;   download, using the VHD management system, the first and the new cloud allocation tables;   merge, at the VHD management system, the first and the new cloud allocation tables to form an updated cloud allocation table; and   upload, using the VHD management system, the updated cloud allocation table to the cloud vendor such that the updated cloud allocation table includes information regarding the changed data blocks in the plurality of data blocks.   
     
     
         9 . The tangible computer-readable storage medium of  claim 8 , wherein the one or more processors are caused to merge by:
 detecting updated cloud object identifiers in the first and the new cloud allocation tables to form updated cloud object identifiers in the updated cloud allocation table.   
     
     
         10 . The tangible computer-readable storage medium of  claim 8 , wherein the one or more processors are caused to determine the changes based upon determining which sectors of the one or more data blocks have changed. 
     
     
         11 . The tangible computer-readable storage medium of  claim 10 , wherein the cloud object identifiers are Boolean indicators in the first and the new cloud allocation tables. 
     
     
         12 . The tangible computer-readable storage medium of  claim 8 , wherein for each data block that is changed in the one or more data blocks, the new cloud object identifiers are created. 
     
     
         13 . The tangible computer-readable storage medium of  claim 8 , wherein the plurality of data blocks store respective snapshots of virtual machine images. 
     
     
         14 . The tangible computer-readable storage medium of  claim 8 , wherein the first cloud allocation and the new cloud allocation tables are smaller in size than the data blocks such that a time taken for the downloading is less than a time taken for downloading the data blocks. 
     
     
         15 . A system for managing virtual hard disks in a cloud computing/storage environment, the system comprising: 
       one or more processors configured to:
 associate, using a virtual hard disk (VHD) management system of a server device, a plurality of data blocks of a virtual hard disk stored at a cloud vendor to a corresponding plurality of cloud objects; 
 store, using the VHD management system, a plurality of cloud object identifiers associated with the plurality of cloud objects in a first cloud allocation table; 
 determine, using the VHD management system, changes to one or more data blocks in the plurality of data blocks; 
 form, using the VHD management system, corresponding new cloud allocation tables for every data block in the plurality of data blocks that has changed, the new cloud allocation tables having corresponding new cloud object identifiers; 
 download, using the VHD management system, the first and the new cloud allocation tables; 
 merge, at the VHD management system, the first and the new cloud allocation tables to form an updated cloud allocation table; and 
 upload, using the VHD management system, the updated cloud allocation table to the cloud vendor such that the updated cloud allocation table includes information regarding the changed data blocks in the plurality of data blocks. 
 
     
     
         16 . The system of  claim 15 , wherein the one or more processors are caused to merge by:
 detecting updated cloud object identifiers in the first and the new cloud allocation tables to form updated cloud object identifiers in the updated cloud allocation table.   
     
     
         17 . The system of  claim 15 , wherein the one or more processors are caused to determine the changes based upon determining which sectors of the one or more data blocks have changed. 
     
     
         18 . The system of  claim 17 , wherein the cloud object identifiers are Boolean indicators in the first and the new cloud allocation tables. 
     
     
         19 . The system of  claim 15 , wherein for each data block that is changed in the one or more data blocks, the new cloud object identifiers are created. 
     
     
         20 . The system of  claim 15 , wherein the plurality of data blocks store respective snapshots of virtual machine images. 
     
     
         21 . The system of  claim 15 , wherein the first cloud allocation and the new cloud allocation tables are smaller in size than the data blocks such that a time taken for the downloading is less than a time taken for downloading the data blocks.