VIRTUAL MAC ADDRESS SYSTEM AND METHOD

• US 20090049199A1
• Filed: 08/15/2008
• Published: 02/19/2009
• Est. Priority Date: 04/22/2002
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Bakke, Mark A., Kuik, Timothy J.
• Granted Patent: US 7,730,210 B2
• Time in Patent Office: Days
• US Class Current: 709/245
• CPC Class Codes: H04L 2101/604 Address structures or formats
• CPC Class Codes: H04L 2101/622 Layer-2 addresses, e.g. medium access control [MAC] addresses
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 45/586 of virtual routers
• CPC Class Codes: H04L 61/10 of different types
• CPC Class Codes: H04L 61/5038 for local use, e.g. in LAN or USB networks, or in a controller area network [CAN]

Abstract

A method for creating a virtual MAC address, the method includes receiving an Internet Protocol address that is to be associated with a virtual MAC address. The method creates a virtual MAC address by setting an OUI portion of the virtual MAC address to an OUI value and setting the non-OUI portion of the virtual MAC address to a subset of the Internet Protocol (IP) address. In one embodiment, the lower three bytes of the IP address are used. Additionally, a method of migrating a virtual MAC address includes detecting a migration event on a first system; creating a virtual MAC address on a second system; and issuing a gratuitous ARP packet containing the virtual MAC address.

Claims

1. A method for creating a virtual MAC address, the method comprising:

configuring in a configuration for a first network attached system a plurality Internet Protocol (IP) addresses for each of a plurality of applications executing on the first network attached system, wherein each of the plurality of applications is provided a different IP address;

replicating the configuration to a second network attached system;

creating a plurality of virtual MAC (Media Access and Control) addresses, each virtual MAC address associated with one of the different IP addresses;

setting a non-OUI portion of the virtual MAC address to a subset of the Internet Protocol (IP) address associated with the virtual MAC address;

detecting a migration event on the first network attached system;

initializing the plurality of applications on the second network attached system according to the replicated configuration, wherein each of the plurality of applications is assigned the different IP address according to the replicated configuration; and

recreating on the second network attached system the plurality of virtual MAC addresses, each virtual MAC address associated with one of the different IP addresses and each created on the second network attached system by setting a non-OUI portion of each virtual MAC address to a subset of the different Internet Protocol (IP) address associated with the virtual MAC address.

2. The method of claim 1, further comprising setting the local bit of an OUI portion of the virtual MAC address.

3. The method of claim 1, wherein the subset of the IP address comprises three bytes.

4. The method of claim 1, wherein the subset of the IP address comprises a subset of the low order bytes of the IP address.

5. The method of claim 1, further comprising

removing the virtual MAC address on the first network interface to be migrated.

7. The method of claim 1, wherein the migration event is a failover event.

6. (canceled)

8. A system comprising:

a first network attached system having a plurality of applications, each application having a different IP address;

a configuration to maintain each of the different IP addresses for the plurality of applications;

a first network interface coupled to the first network attached system, the first network interface configured with a plurality of MAC addresses, wherein a MAC address of the plurality of MAC addresses is associated with the different IP address of one of the plurality of applications; and

a second network attached system having a second network interface coupled to the network and operable to;

receive a replicated configuration corresponding to the configuration on the first network attached system,

in response to a migration event, initialize on the second network attached system the plurality of applications according to the replicated configuration, wherein each of the plurality of applications is assigned the different IP address according to the replicated configuration, and

recreate on the second network attached system the plurality of virtual MAC addresses, each virtual MAC address associated with one of the different IP addresses;

wherein each MAC address of the plurality of MAC addresses includes a non-OUI portion that comprises a subset of the different IP address associated with the MAC address.

9. The system of claim 8, wherein the local bit of an OUI portion of each virtual MAC address is set.

10. The system of claim 8, wherein the subset of the IP address comprises three bytes.

11. The system of claim 8, wherein the subset of the IP address comprises a subset of the low order bytes of the IP address associated with the MAC address.

12. The system of claim 8, wherein the migration event comprises a failure of one or more of the plurality of applications in the first network attached system.

13. A computer-readable storage medium having stored thereon a method for creating a virtual MAC address, the method comprising:

configuring in a configuration for a first network attached system a plurality Internet Protocol (IP) addresses for each of a plurality of applications executing on the first network attached system, wherein each of the plurality of applications is provided a different IP address;

replicating the configuration to a second network attached system;

creating a plurality of virtual MAC (Media Access and Control) addresses, each virtual MAC address associated with one of the different IP addresses;

setting a non-OUI portion of the virtual MAC address to a subset of the Internet Protocol (IP) address-associated with the virtual MAC address;

detecting a migration event on the first network attached system;

initializing the plurality of applications on the second network attached system according to the replicated configuration, wherein each of the plurality of applications is assigned the different IP address according to the replicated configuration; and

recreating on the second network attached system the plurality of virtual MAC addresses, each virtual MAC address associated with one of the different IP addresses and each created on the second network attached system by setting a non-OUI portion of each virtual MAC address to a subset of the different Internet Protocol (IP) address associated with the virtual MAC address.

14. The computer-readable storage medium of claim 13, wherein the method further comprises setting the local bit of an OUI portion of the virtual MAC address.

15. The computer-readable storage medium of claim 13, wherein the subset of the IP address comprises three bytes.

16. The computer-readable storage medium of claim 13, wherein the subset of the IP address comprises a subset of the low order bytes of the IP address.

17. The computer-readable storage medium of claim 13, wherein the method further comprises removing the virtual MAC address on the first network interface to be migrated.

18. The computer-readable storage medium of claim 13, wherein the migration event is a failover event.

19. A system comprising:

means for configuring in a configuration for a first network attached system an IP address for each of a plurality of applications on the first network attached system, wherein each applications is provided a different IP address;

means for replicating the configuration to a second network attached system;

means for creating a plurality of virtual MAC address, each virtual MAC address associated with one of the different IP addresses;

means for setting a non-OUI portion of each virtual MAC address to a subset of the different IP address associated with the virtual MAC address

means for detecting a migration event on the first network attached system;

means for initializing on the second network attached system the plurality of applications according to the replicated configuration, wherein each of the plurality of applications is assigned the different IP address according to the replicated configuration; and

means for recreating on the second network attached system the plurality of virtual MAC addresses, each virtual MAC address associated with one of the different IP addresses and each created on the second network attached system by setting a non-OUI portion of each virtual MAC address to a subset of the different Internet Protocol (IP) address associated with the virtual MAC address.