Online virtual machine disk migration

Patent metadata

Field	Value
Publication number	US-10007463-B2
Application number	US-201615182521-A
Country	US
Kind code	B2
Filing date	Jun 14, 2016
Priority date	Jul 31, 2007
Publication date	Jun 26, 2018
Grant date	Jun 26, 2018

Abstract

A method for migrating a virtual machine disk (VM disk) from first physical storage to second physical storage while the virtual machine (VM) is running, the method comprising: (a) creating a first child VM disk to which writes are redirected from a first parent VM disk, the first parent VM disk being on the first physical storage; (b) copying the first parent VM disk to the second physical storage as a second parent VM disk; (c) re-parenting the first VM child disk to the second parent VM disk; and (d) consolidating the first child VM disk and the second parent VM disk.

First claim

What is claimed is:

1. A method for migrating a virtual machine disk (VM disk) from first physical storage to second physical storage while the virtual machine (VM) is maintained in its physical location, the method comprising:
creating on the second physical storage, a first child VM disk to which writes directed to a first parent VM disk are redirected, the first parent VM disk being on the first physical storage;
copying the first parent VM disk to the second physical storage as a second parent VM disk;
re-parenting the first child VM disk to the second parent VM disk; and
consolidating the first child VM disk and the second parent VM disk on the second physical storage;
wherein the first parent VM disk on which the VM is dependent for execution is migrated from the first physical storage to the second physical storage while the VM is running without migrating the VM.

2. The method of claim 1 , further comprising deleting the first parent VM disk from the first physical storage without migrating the VM, such that the VM has remained in its physical location while the first parent VM disk on which the VM is dependent for execution has been migrated.

3. The method of claim 1 , further comprising, after the first child VM disk is created:
designating the first parent VM disk as read-only; and
redirecting writes intended for the first parent VM disk to the first child VM disk.

4. The method of claim 1 , further comprising, prior to consolidating:
directing a read intended for the first parent VM disk to the first child VM disk if information associated with the read is unavailable in the first parent VM disk.

5. The method of claim 1 , wherein the first child VM disk is represented as a file or as a raw device mapping.

6. The method of claim 1 , wherein the first parent VM disk is represented as a file or as a raw device mapping.

7. The method of claim 1 , further comprising:
taking a snapshot of the first child VM disk, whereby a second child VM disk is created on physical storage;
redirecting writes intended for the first child VM disk to the second child VM disk; and
subsequent to consolidating the first child VM disk and the second parent VM disk, consolidating the second child VM disk and the second parent VM disk.

8. The method of claim 7 , further comprising, prior to consolidating:
directing a read intended for the first parent VM disk to the first child VM disk if information associated with the read is unavailable in the first parent VM disk; and
directing the read to the second child VM disk if the information is unavailable in the first child VM disk.

9. The method of claim 1 , further comprising migrating the virtual machine from a first host platform to a second host platform before or after the VM disk is migrated.

10. The method of claim 1 , wherein said virtual machine comprises a template, wherein said first child VM disk comprises information that customizes said template.

11. The method of claim 1 , wherein creating a first child VM disk comprises taking a snapshot of the first parent VM disk.

12. A non-transitory computer-readable medium having computer-executable instructions for causing a virtualized computer system to perform a method for migrating a virtual machine disk (VM disk) from first physical storage to second physical storage while the virtual machine (VM) is maintained in its physical location, the method comprising:
creating a first child VM disk to which writes directed to a first parent VM disk are redirected, the first parent VM disk being on the first physical storage;
copying the first parent VM disk to the second physical storage as a second parent VM disk;
re-parenting the first child VM disk to the second parent VM disk; and
consolidating the first child VM disk and the second parent VM disk on the second physical storage;
wherein the first parent VM disk on which the VM is dependent for execution is migrated from the first physical storage to the second physical storage while the VM is running without migrating the VM.

13. The computer-readable medium of claim 12 , wherein the method further comprises deleting the first parent VM disk from the first physical storage without migrating the VM, such that the VM has remained in its physical location while the first parent VM disk on which the VM is dependent for execution has been migrated.

14. The computer-readable medium of claim 12 , wherein the method further comprises, after the first child VM disk is created:
designating the first parent VM disk as read-only; and
redirecting writes intended for the first parent VM disk to the first child VM disk.

15. The computer-readable medium of claim 12 , wherein the method further comprises, prior to consolidating:
directing a read intended for the first parent VM disk to the first child VM disk if information associated with the read is unavailable in the first parent VM disk.

16. The computer-readable medium of claim 12 , wherein the first child VM disk is represented as a file or as a raw device mapping.

17. The computer-readable medium of claim 12 , wherein the first parent VM disk is represented as a file or as a raw device mapping.

18. The computer-readable medium of claim 12 , wherein the method further comprises:
taking a snapshot of the first child VM disk, whereby a second child VM disk is created on physical storage;
redirecting writes intended for the first child VM disk to the second child VM disk; and
subsequent to consolidating the first child VM disk and the second parent VM disk, consolidating the second child VM disk and the second parent VM disk.

19. The computer-readable medium of claim 12 , wherein the first child VM disk is created on the second physical storage.

20. The computer-readable medium of claim 12 , wherein creating a first child VM disk comprises taking a snapshot of the first parent VM disk.

Assignees

• Vmware Inc

Inventors

• Colbert Osten Kit
• Hutchins Gregory
• Bosch Robert
• Ranganathan Jairam
• Baxter Joel

Classifications

• G06F3/0689

  Disk arrays, e.g. RAID, JBOD · CPC title

• G06F3/0617

  in relation to availability · CPC title

• G06F3/0619

  in relation to data integrity, e.g. data losses, bit errors · CPC title

• G06F3/067

  Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS] · CPC title

• G06F11/1471

  involving logging of persistent data for recovery · CPC title