Method and apparatus for transparently providing a failover network device
AssigneeCisco Technology, Inc.
InventorsBrantley W. Coile, James A. Jordan
Life of this patent
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Abstract
A system and method are disclosed for transferring a network function from a primary network device to a backup network device. The backup network device first detects that the primary network device has failed. The backup network device then sends a message to the primary network device indicating to the primary network device that the primary network device has failed. The IP address of the backup network device changes from a standby IP address to an active IP address, and the IP address of the primary network device changes from the active IP address to the standby IP address. Packets sent to the active IP address are then handled with the backup network device.
Claims24
A method of transferring a network function from a primary network device to a backup network device comprising:
- detecting at the backup network device mapped to a standby IP address that the primary network device mapped to an active IP address has failed;
- sending a message from the backup network device to the primary network device indicating to the primary network device that the primary network device has failed;
- mapping the IP address of the backup network device from the standby IP address to the active IP address;
- mapping the IP address of the primary network device from the active IP address to the standby IP address;
- and
- handling packets sent to the active IP address with the backup network device.
A hot standby network device for backing up a primary network device comprising:
- means for detecting that the primary network device mapped to an active IP address has failed;
- means for sending a message from the hot standby network device indicating that the primary network device has failed so that the active IP address will become available to the hot standby network device;
- means for mapping the local IP address of the hot standby network device from a standby IP address to an active IP address;
- and
- means for handling packets sent to the active IP address with the hot standby network device.
A standby network device comprising:
- a processor configured to detect that a primary network device mapped to a active IP address has failed;
- an interface configured to send a message from the backup network device to the primary network device indicating to the primary network device that the primary network device has failed;
- a memory configured to map the IP address of the backup network device from the standby IP address to the active IP address;
- wherein the processor is further configured to handle packets sent to the active IP address when the IP address of the backup network device is mapped to the active IP address.
A primary network device comprising:
- an interface configured to receive a message from a backup network device mapped to a standby IP address indicating to the primary network device that the primary network device has failed;
- a processor configured to detect that the primary network device should be failed as a result of the receipt of the message from the backup network device;
- a memory configured to map the IP address of the primary network device from the active IP address to the standby IP address;
- wherein the processor is further configured to handle packets sent to the standby IP address when the IP address of the primary network device is mapped to the standby IP address.
Dependencies are inferred from the claim text.