Synchronization of a virtual storage system and an actual storage system

• US 8,438,346 B2
• Filed: 04/27/2006
• Issued: 05/07/2013
• Est. Priority Date: 04/27/2006
• Status: Expired due to Fees

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Gold, Stephen
• Primary Examiner(s): Alsip, Michael
• Application Number:
  US11/412,485
• Publication Number:
  US 20070255920A1
• Time in Patent Office: 2,567 Days
• Field of Search: None
• US Class Current: 711/162
• CPC Class Codes: G06F 11/1458 Management of the backup or restore process
• CPC Class Codes: G06F 3/0611 in relation to response time
• CPC Class Codes: G06F 3/0653 Monitoring storage devices or systems
• CPC Class Codes: G06F 3/0664 at device level, e.g. emulation of a storage device or system
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: G06F 3/0686 Libraries, e.g. tape libraries, jukebox

Abstract

A virtual storage system includes a storage subsystem having virtual storage devices to emulate physical storage devices of an actual storage system. The virtual storage system has a controller to detect a status change of a particular physical storage device in the actual storage system. The status change includes at least one of loading of the particular physical storage device and ejecting of the particular physical storage device. In response to detecting the status change of the particular physical storage device, the controller performs synchronization between the virtual storage system and the actual storage system by updating a state of a corresponding virtual storage device in the virtual storage system.

Claims

1. A virtual storage system comprising:

a storage subsystem having virtual storage devices to emulate physical storage devices of an actual storage system; and

a controller to;

detect a status change of a particular physical storage device in the actual storage system, the status change comprising at least one of loading of the particular physical storage device and ejecting of the particular physical storage device; and

in response to detecting the status change of the particular physical storage device, perform synchronization between the virtual storage system and the actual storage system by updating a state of a corresponding virtual storage device in the virtual storage system,

wherein the controller is configured to update the state of the corresponding virtual storage device by;

in response to the particular physical storage device being loaded in the actual storage system, checking whether the corresponding virtual storage device exists in the virtual storage system; and

in response to determining that the corresponding virtual storage device does not exist in the virtual storage system, creating the corresponding virtual storage device.

2. The virtual storage system of claim 1, wherein the controller is configured to update the state of the corresponding virtual storage device by further:

setting the corresponding virtual storage device to a writable state from a read-only state in response to determining that the corresponding virtual storage device exists.

3. The virtual storage system of claim 1, wherein the controller is configured to create the corresponding virtual storage device by:

accessing a collection of header information to determine whether header information for the loaded physical storage device is present;

in response to the header information for the loaded storage device being present in the collection, adding the header information for the loaded physical storage device to the corresponding virtual storage device; and

in response to the header information for the loaded storage device not being present in the collection, triggering a scan of a header of the loaded physical storage device to copy information from the header to the corresponding virtual storage device.

4. The virtual storage system of claim 1, wherein loading of the physical storage device is performed for one of an overwrite operation and a restore operation, and wherein the controller is configured to trigger a reverse copy operation to copy data from the loaded physical storage device to the corresponding virtual storage device in response to detecting that the loading is performed for the restore operation.

5. The virtual storage system of claim 1, wherein the created corresponding virtual storage device has metadata identical to metadata of the loaded physical storage device.

6. The virtual storage system of claim 5, wherein the metadata includes an identifier of the loaded physical storage device, a type of the physical storage device, and a size of the physical storage device.

7. The virtual storage system of claim 1, wherein the controller is configured to monitor the actual storage system to detect ejection of the particular physical storage device from the actual storage system, and to update the state of the corresponding virtual storage device by moving the virtual storage device to a predefined location in response to detecting ejection of the particular physical storage device from the actual storage system.

8. The virtual storage system of claim 1, wherein, in response to detecting ejection of the particular physical storage device from the actual storage system, the controller is configured to:

check whether a copy job is pending for the ejected physical storage device; and

if a copy job is pending for the ejected physical storage device, set an error condition.

9. The virtual storage system of claim 1, wherein the controller is configured to update the state of the corresponding virtual storage device in response to detecting ejection of the particular physical storage device from the actual storage system by setting the virtual storage device to a read-only state.

10. The virtual storage system of claim 1, wherein the controller is configured to update the state of the corresponding virtual storage device in response to detecting ejection of the particular physical storage device from the actual storage system by setting an expiry time for the corresponding virtual storage device.

11. The virtual storage system of claim 10, wherein the controller is configured to check for expiration of the expiry time, and in response to expiration of the expiry time, the controller is configured to delete the corresponding virtual storage device.

12. The virtual storage system of claim 1, wherein, in response to detecting ejection of the particular physical storage device from the actual storage system, the controller is configured to:

check whether the corresponding virtual storage device is in a virtual drive; and

if the corresponding virtual storage device is in the virtual drive, set an error condition.

13. The virtual storage system of claim 1, wherein the controller is configured to further:

detect a data state change in one or more virtual storage devices in the virtual storage system; and

copy content of the one or more virtual storage devices to respective one or more physical storage devices in the actual storage system in response to the data state change.

14. A method for use with a virtual storage system having virtual storage devices for emulating physical storage devices of an actual storage system, comprising:

detecting loading of a physical storage device in the actual storage system;

in response to detecting loading of the physical storage device, perform synchronization between the virtual storage system and the actual storage system by checking whether a corresponding virtual storage device exists in the virtual storage system, and in response to determining that the corresponding virtual storage device does not exist in the virtual storage system, creating the corresponding virtual storage device.

15. The method of claim 14, further comprising:

in response to detecting data change on a particular virtual storage device in the virtual storage system, performing automigration to copy data from the particular virtual storage device to a corresponding physical storage device in the actual storage system.

16. The method of claim 15, wherein performing the automigration is performed transparently to a backup application executable on a backup server that is separate from the virtual storage system.

17. The method of claim 14, further comprising:

in response to detecting one of loading of a particular physical storage device and ejection of the particular physical storage device, performing at least one of;

maintaining consistency of data between the particular physical storage device and a particular virtual storage device; and

generating an error condition to indicate that the particular physical storage device is not synchronized with respect to the particular virtual storage device.

18. The method of claim 14, further comprising:

monitoring the actual storage system to detect ejection of a particular physical storage device from the actual storage system; and

in response to detecting the ejection of the particular physical storage device, moving a corresponding virtual storage device in the virtual storage system to a predefined location of the virtual storage system.

19. An article comprising at least one storage medium containing instructions that when executed cause a virtual library system to:

monitor an actual storage system having physical storage devices to detect ejection of a particular one of the physical storage devices;

in response to detecting ejection of the particular physical storage device, perform an action with respect to a virtual storage device in the virtual library system that corresponds to the particular physical storage device to maintain synchronization between the virtual storage device and the particular physical storage device;

detect loading of a second physical storage device into the actual storage system;

in response to detecting loading of the second physical storage device, check whether a corresponding second virtual storage device exists in the virtual storage system; and

in response to determining that the corresponding second virtual storage device does not exist in the virtual storage system, create the corresponding second virtual storage device.