Storage area network access for virtual machines

• US 8,166,475 B1
• Filed: 06/29/2006
• Issued: 04/24/2012
• Est. Priority Date: 12/30/2005
• Status: Active Grant

• Current Assignee: Vmware LLC (Broadcom, Inc.)
• Original Assignee: VMware, Inc. (Broadcom, Inc.)
• Inventors: Scales, Daniel J., Mahalingam, Mallik
• Primary Examiner(s): Tang, Kenneth
• Application Number:
  US11/478,200
• Time in Patent Office: 2,126 Days
• Field of Search: 718/1, 711/114, 709/223
• US Class Current: 718/1
• CPC Class Codes: G06F 9/455 Emulation; Interpretation; Software simulation, e.g. virtualisation or emulation of application or operating system execution engines
• CPC Class Codes: G06F 9/45558 Hypervisor-specific management and integration aspects
• CPC Class Codes: H04L 67/1097 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]

Abstract

Detailed herein are approaches to allowing individual virtual machines executing on a single physical host to have their own substantially unique identifier for access to a storage area network (SAN). In one approach, a substantially unique identifier (SUI) is associated with a virtual machine, and the physical node is instructed to use that SUI when logging into the SAN and when performing input or output operations on behalf of the virtual machine.

Claims

1. A method of allowing a virtual machine (VM), executing on a physical node, to access a storage area network (SAN), comprising:

associating a unique identifier with said VM, wherein said unique identifier differs from other unique identifiers associated with other VMs executing on the physical node; and

when dynamic unique identifier addressing is supported such that a host bus adapter (HBA) of the physical node is allowed to dynamically use different unique identifiers to access logical unit numbers (LUNs), instructing said physical node to use said unique identifier associated with said VM, rather than a unique identifier associated with said HBA of the physical node, when communicating with a logical unit number (LUN) associated with said VM and stored in said SAN in order to perform an input/output operation for said VM, wherein said LUN is allocated for access to said VM based on the use of the unique identifier and said LUN is not accessible by other VMs with different unique identifiers that are executing on the physical node.

2. The method of claim 1, wherein said SAN comprises a Fibre Channel storage area network.

3. The method of claim 2, wherein said unique identifier comprises a worldwide name (WWN).

4. The method of claim 1, wherein said SAN comprises an Internet small computer system interface (iSCSI).

5. The method of claim 4, wherein said unique identifier comprises an iSCSI initiator name.

6. The method of claim 1, wherein said associating is performed at the time of virtual machine creation.

7. The method of claim 1, wherein said associating is performed after virtual machine creation but before the VM is first loaded into a host.

8. The method of claim 1, wherein said unique identifier is recorded as part of a virtual machine configuration file associated with said VM.

9. A virtual machine cluster, comprising:

a physical node, configured to host a virtual machine (VM);

a virtual machine management console, coupled to said physical node, configured to create and manage said virtual machine; and

a storage area network (SAN), coupled to said physical node, and configured to provide access to a logical unit number block (LUN) associated with said VM,

wherein said virtual machine management console, upon creation of said VM, assigns a unique identifier to said virtual machine that differs from other unique identifiers associated with other VMs executing on the physical node, and wherein when dynamic unique identifier addressing is supported such that a host bus adapter (HBA) of the physical node is allowed to dynamically use different unique identifiers to access LUNs, said physical node uses said unique identifier, rather than a unique identifier associated with said HBA of the physical node, to provide said virtual machine access to said LUN, wherein said LUN is allocated for access to said VM based on the use of the unique identifier and said LUN is not accessible by other VMs with different unique identifiers that are executing on the physical node.

10. The virtual machine cluster of claim 9, wherein said virtual machine management console determines if said HBA can be dynamically configured to use said unique identifier.

11. The virtual machine cluster of claim 10, wherein said HBA is configured for use with a Fibre Channel SAN, and said unique identifier comprises a worldwide name (WWN).

12. The virtual machine cluster of claim 10, wherein said HBA is configured for use with an Internet small computer system interface (iSCSI), and said unique identifier comprises an iSCSI initiator name.

13. The virtual machine cluster of claim 9, wherein said virtual machine management console is configured to create and manage said other VMs.

14. The virtual machine cluster of claim 13, wherein said physical node uses a particular unique identifier associated with a particular VM, to provide said particular VM access to a particular LUN in the SAN associated with said particular VM.

15. The virtual machine cluster of claim 14, wherein said physical node maintains a virtual machine unique identifier table, for correlating said unique identifiers with said VMs.

16. A non-transitory computer-usable medium having computer-readable program code embodied therein for causing a computer system to execute a method of physical node operation, comprising:

loading a virtual machine into a physical node, said virtual machine having an associated unique identifier that differs from other unique identifiers associated with other virtual machines executing on the physical node;

when dynamic unique identifier addressing is supported such that a host bus adapter (HBA) of the physical node is allowed to dynamically use different unique identifiers to access logical unit numbers (LUNs), connecting to a storage area network (SAN), using said unique identifier associated with said VM, rather than a unique identifier associated with said HBA of the physical node, in order to perform an I/O action with a logical unit number (LUN) associated with the virtual machine and stored in the SAN, wherein said LUN is allocated for access to said VM based on the use of the unique identifier and said LUN is not accessible by other VMs with different unique identifiers that are executing on the physical node.

17. The non-transitory computer-usable medium of claim 16, further comprising:

determining if said SAN is currently accessible.

18. The non-transitory computer-usable medium of claim 16, further comprising:

determining if the host bus adapter (HBA) used to access said SAN supports dynamic unique identifier addressing.

19. The non-transitory computer-usable medium of claim 16, further comprising:

determining if said SAN supports dynamic unique identifier addressing.

20. The non-transitory computer-usable medium of claim 16, further comprising:

determining if a disk array attached to said SAN supports dynamic unique identifier addressing.

21. The non-transitory computer-usable medium of claim 20, further comprising:

using said unique identifier to access a portion of said disk array associated with said virtual machine, in order to perform a maintenance action.

22. The non-transitory computer-usable medium of claim 16, further comprising:

using said unique identifier to log off of said SAN.

23. A method of virtual machine migration, comprising:

powering down a virtual machine (VM) on a first host system, said virtual machine having an associated unique identifier for accessing a logical unit number block (LUN) on a storage area network (SAN), wherein said LUN is associated with said VM and said unique identifier differs from other unique identifiers associated with other VMs executing on the first host system or a second host system;

loading said virtual machine onto the second host system;

powering on said virtual machine on said second host system; and

when dynamic unique identifier addressing is supported such that a host bus adapter (HBA) of said second host system is allowed to dynamically use different unique identifiers to access LUNs, using said unique identifier, rather than a unique identifier associated with said HBA of the second host system, to access said LUN on said SAN from said second host system, wherein said LUN is allocated for access to said VM based on the use of the unique identifier and said LUN is not accessible by other VMs with different unique identifiers that are executing on the first host system or the second host system.

24. The method of claim 23, further comprising:

updating a VM unique identifier table in said first host system to remove a reference to said unique identifier.

25. The method of claim 23, further comprising:

logging said first host system out of said SAN using said unique identifier.

26. The method of claim 23, further comprising:

updating a VM unique identifier table in said second host system to add a reference to said unique identifier.

27. The method of claim 23, further comprising:

unloading said virtual machine from said first host system.