Virtualization metadata promotion

• US 7,805,565 B1
• Filed: 12/23/2005
• Issued: 09/28/2010
• Est. Priority Date: 12/23/2005
• Status: Active Grant

• Current Assignee: Oracle America, Inc. (Oracle Corporation)
• Original Assignee: Oracle America, Inc. (Oracle Corporation)
• Inventors: Hill, Dawn, Panuganty, Ramesh, Milligan, Charles
• Primary Examiner(s): Thai; Tuan V
• Assistant Examiner(s): Rojas; Midys
• Application Number:
  US11/317,137
• Time in Patent Office: 1,740 Days
• Field of Search: 711/114, 711/203, 711/206, 707/999.001, 707/999.01, 707/999.107, 707/999.2, 707/999.202, 707/999.204, 710/5
• US Class Current: 711/114
• CPC Class Codes: G06F 11/0727 in a storage system, e.g. in a DASD or network based storage system drivers for digital recording or reproducing units G06F3/06; circuits for error detection or correction within digital recording or reproducing units G11B20/18; for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS], H04L67/1097
• CPC Class Codes: G06F 11/0793 Remedial or corrective actions recovery from an exception in an instruction pipeline G06F9/3861; by retry G06F11/1402; for recovering from a failure of a protocol instance or entity H04L69/40
• CPC Class Codes: G06F 3/0617 in relation to availability
• CPC Class Codes: G06F 3/0664 at device level, e.g. emulation of a storage device or system
• CPC Class Codes: G06F 3/0683 Plurality of storage devices

Abstract

A method for storing digital data in a virtualization storage system which includes the step of creating a virtual storage volume and communicating the location of the virtual storage volume to a storage subsystem. The storage subsystem identifies a mapping type between the virtual volume and at least one virtual volume-related physical device and then creates virtualization metadata describing the virtual volume, the mapping type, and the virtual volume-related physical device. The storage subsystem mediates the storing of at least a portion of the virtualization metadata on the virtual volume-related physical device as device stored metadata. A portion of the stored virtualization metadata is provided to then one or more using systems which utilize this metadata to update the virtual volume information contained therein. A virtualization storage system implements one or more steps of the methods of the invention.

Claims

1. A method for storing digital data in a virtualization storage system having one or more using systems having virtual volume mappings, a storage subsystem, and one or more physical storage devices, the method comprising:

a) creating a virtual storage volume;

b) communicating the location of the virtual storage volume to the storage subsystem;

c) identifying a mapping type between the virtual volume and at least one virtual volume-related physical device;

d) creating virtualization metadata describing the virtual volume, the mapping type, and the virtual volume-related physical device; and

e) associating at least a portion of the virtualization metadata with the virtual volume-related physical device;

f) providing at least a portion of the stored virtualization metadata to the using system; and

g) updating virtual volume information in the using system such that the using system responds to a request for specified data stored by allowing the using system to access the specified data that was originally requested by direct access to the at least one virtual volume related physical device if the storage subsystem is unable to identify the virtual volume-related physical device as a result of a failure of the virtual volume.

2. The method of claim 1 further comprising:

h) receiving a read access request to the virtual volume;

i) identifying the virtual volume-related physical device from the virtualization metadata;

j) preparing the virtual volume-related physical device identified in step h) for access; and

k) honoring the read access request.

3. The method of claim 2 wherein if the virtual volume-related physical device cannot be identified in step i) the using system makes direct access to the at least one virtual volume related device using the virtual volume information stored thereon.

4. The method of claim 3 wherein the virtualization metadata provided in step f is found by:

l) scanning the one or more physical storage devices for the device stored metadata to identify the virtual volume-related physical device corresponding to the virtual volume;

m) relating the virtual volume-related physical device identified in step l) to the virtual volume.

5. The method of claim 3 wherein if the virtual volume-related physical device cannot be identified in step i), the using systems make direct access to the virtual volume-related physical device.

6. The method of claim 1 wherein the mapping type is a RAID, a disk enclosure, a mirror of a storage devices, technology substitution, log structure file virtualization, heap virtualization, managed array of individual devices, random array of independent tapes, random array of independent libraries, local or remote segmentation copies, and combinations thereof.

7. The method of claim 1 wherein the virtualization data is stored within the storage subsystem.

8. The method of claim 1 wherein the storage subsystem is a system selected from the group consisting of disk virtualization systems, tape virtualization systems, multilevel hierarchy systems using disk, disk and tape, disk and optical disk, or any combination of disk, tape, optical, magneto-optical, holographic, solid state, nano-devices, or multi-media storage, systems using automated libraries of devices and-or storage media, non-automated management systems using removable media and devices sent to remote locations, and combinations thereof.

9. A virtualization storage system comprising:

one or more physical storage devices;

a storage subsystem operable to;

receive the location of a virtual storage volume to the storage subsystem;

identify a mapping type between the virtual volume and a virtual volume-related physical device;

create virtualization metadata describing the virtual volume, the mapping type, and the virtual volume-related physical device;

store at least a portion of the virtualization metadata on the virtual volume-related physical device as device stored metadata; and

provide the virtualization metadata to one or more using systems so that virtual volume information stored therein is updated allowing the using system to make subsequent direct access to the at least one virtual volume related physical device as a solution to the failure of a virtual volume.

10. The virtualization storage system of claim 9 wherein the storage subsystem is further operable to:

receive a read access request to the virtual volume;

identify the virtual volume-related physical device from the virtualization metadata; and

preparing the virtual volume-related physical device for access.

11. The virtualization storage system of claim 9 wherein the storage subsystem is further operable to:

scan the one or more physical storage devices for the device stored metadata to identify the virtual volume-related physical device corresponding to the virtual volume; and

relate the virtual volume-related physical device identified in step k) to the virtual volume.

12. The virtualization storage system of claim 9 wherein the storage subsystem is further operable to:

communicate an identifier for the virtual volume-related physical device to the host, wherein the host stores the identifier as a synonym for the virtual volume.

13. The virtualization storage system of claim 12 wherein the storage subsystem is further operable to:

scan the one or more physical storage devices for the device stored metadata to identify the virtual volume-related physical device corresponding to the virtual volume; and

relate the virtual volume-related physical device to the virtual volume.

14. A method for a using system to access, via a storage subsystem, data stored in a virtualized storage system having virtualization metadata to map a virtual storage volume to one or more physical storage devices, the method comprising:

scanning the one or more physical storage devices for virtualization metadata relating to a requested virtual volume in response to the storage subsystem being unable to identify one or more physical storage devices from the virtualization metadata associated with a requested virtual volume identified by the storage subsystem in response to a request from the using system for data access;

communicating an identifier for the physical storage device containing the virtualization metadata to the using system for subsequent direct access to the physical storage device by the using system.

15. The method of claim 14 further comprising:

storing at least a portion of the virtualization metadata on the one or more physical storage devices prior to scanning.

16. The method of claim 14 wherein communicating an identifier comprises:

identifying a companion physical device associated with the one or more physical devices containing the virtualization metadata; and

communicating an identifier that identifies the companion physical device to the using system.

17. The method of claim 16 further comprising:

directly accessing the companion physical device from the using system via the identifier.

18. The method of claim 14 further comprising:

generating a synonym equating the virtual volume to the physical storage device containing the virtualization metadata based on the identifier for subsequent direct access to the physical storage device in response to a request for data from the virtual volume.