Increased availability on routers through detection of data path failures and subsequent recovery

• US 20060056303A1
• Filed: 09/14/2004
• Published: 03/16/2006
• Est. Priority Date: 09/14/2004
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Kumar, Ashok, Honnavalli, Shrinath, Bhatt, Nimish, Aggarwal, Amit Kumar, Arora, Sumeet Knmar, Dattathri, Venkatesh, Bhardwaj, Sahil Chander
• Granted Patent: US 7,489,643 B2
• Time in Patent Office: Days
• US Class Current: 370/248
• CPC Class Codes: H04L 41/0668 by dynamic selection of recovery network elements, e.g. replacement by the most appropriate element after failure
• CPC Class Codes: H04L 41/0677 Localisation of faults
• CPC Class Codes: H04L 43/00 Arrangements for monitoring or testing data switching networks
• CPC Class Codes: H04L 43/10 Active monitoring, e.g. heartbeat, ping or trace-route
• CPC Class Codes: H04L 43/16 Threshold monitoring
• 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

Abstract

Methods and systems for monitoring a data path on a network routing device are described. The data path includes a plurality of devices on the network routing device and an interface. Data packets are moved on the network routing device using the devices and communicated to and from a network via the interface. A process for detecting a defective device on the network routing device is executed. The process is a self-contained process that is executed within the data path, allowing a defect in the data path to be detected, localized and recovered from.

Claims

1. A method of monitoring a network routing device, said method comprising:

enabling a data path on said network routing device, said data path comprising a plurality of devices on said network routing device and an interface, wherein data packets are moved on said network routing device using said devices and communicated to and from a network via said interface; and

executing a process for detecting a defective device in said plurality of devices, wherein said process is executed within said data path allowing a defect in said data path to be detected, localized and recovered.

2. The method of claim 1 wherein said process comprises:

inserting a loop-back packet into a channel, wherein the destination specified for said loop-back packet is the same as the source of said loop-back packet causing said loop-back packet to travel from said source and back to said source through said devices on said network routing device; and

detecting whether said loop-back packet is received back at said source.

3. The method of claim 2 wherein said channel is dedicated to carrying said loop-back packet.

4. The method of claim 2 further comprising:

inserting into said channel a plurality of loop-back packets at periodic intervals; and

identifying a potential defect on said network routing device when the difference between the number of loop-back packets inserted and the number of loop-back packets received at said source exceeds a threshold.

5. The method of claim 4 further comprising, in response to said identifying of said potential defect, determining whether said data packets are flowing through said interface.

6. The method of claim 1 wherein said process comprises:

accessing information that indicates the number of data packets that are flowing through said interface; and

identifying a potential defect on said network routing device when said information indicates that said number of data packets is not increasing.

7. The method of claim 1 further comprising, in response to identifying a potential defect, performing a diagnostic test of said devices on said network routing device.

8. The method of claim 1 further comprising switching to a redundant network routing device in response to identifying a potential defect.

9. The method of claim 8 wherein there is a limit to the number of times said switching can occur.

10. A computer-usable medium having computer-readable program code embodied therein for causing a controller to perform a method of monitoring a network routing device, said method comprising:

enabling a data path on said network routing device, said data path comprising a plurality of devices on said network routing device and an interface, wherein data packets are moved on said network routing device using said devices and communicated to and from a network via said interface; and

executing a process for detecting a defective device in said plurality of devices, wherein said process is executed within said data path allowing a defect in said data path to be detected, localized and recovered.

11. The computer-usable medium of claim 10 wherein said computer-readable program code embodied therein causes said controller to perform said method further comprising:

inserting a loop-back packet into a channel, wherein the destination specified for said loop-back packet is the same as the source of said loop-back packet causing said loop-back packet to travel from said source and back to said source through said devices on said network routing device; and

detecting whether said loop-back packet is received back at said source.

12. The computer-usable medium of claim 11 wherein said channel is dedicated to carrying said loop-back packet.

13. The computer-usable medium of claim 11 wherein said computer-readable program code embodied therein causes said controller to perform said method further comprising:

inserting into said channel a plurality of loop-back packets at periodic intervals; and

identifying a potential defect on said network routing device when the difference between the number of loop-back packets inserted and the number of loop-back packets received at said source exceeds a threshold.

14. The computer-usable medium of claim 10 wherein said computer-readable program code embodied therein causes said controller to perform said method further comprising, in response to said identifying of said potential defect, determining whether said data packets are flowing through said interface.

15. The computer-usable medium of claim 10 wherein said computer-readable program code embodied therein causes said controller to perform said method further comprising:

accessing information that indicates the number of data packets that are flowing through said interface; and

identifying a potential defect on said network routing device when said information indicates that said number of data packets is not increasing.

16. The computer-usable medium of claim 10 wherein said computer-readable program code embodied therein causes said controller to perform said method further comprising, in response to identifying a potential defect, performing a diagnostic test of said devices on said network routing device.

17. The computer-usable medium of claim 10 wherein said computer-readable program code embodied therein causes said controller to perform said method further comprising switching to a redundant network routing device in response to identifying a potential defect.

18. The computer-usable medium of claim 17 wherein there is a limit to the number of times said switching can occur.

19. A system for monitoring a network routing device, said system comprising:

means for moving, on said network routing device, data packets that are communicated to and from a network, said means for moving comprising a data path on said network routing device;

means for interfacing said network routing device and said network; and

means for implementing a process for detecting a defect in said means for moving data packets, wherein said process is executed within said data path allowing a defect in said data path to be detected, localized and recovered.

20. The system of claim 19 further comprising:

means for inserting a loop-back packet into a channel, wherein the destination specified for said loop-back packet is the same as the source of said loop-back packet causing said loop-back packet to travel from said source and back to said source via said means for moving data packets; and

means for detecting whether said loop-back packet is received back at said source.

21. The system of claim 20 wherein said channel is dedicated to carrying said loop-back packet.

22. The system of claim 20 further comprising:

means for inserting into said channel a plurality of loop-back packets at periodic intervals; and

means for identifying a potential defect on said data path when the difference between the number of loop-back packets inserted and the number of loop-back packets received at said source exceeds a threshold.

23. The system of claim 22 further comprising means for determining, in response to identification of said potential defect, whether said data packets are flowing through said interface.

24. The system of claim 19 further comprising:

means for reading information that indicates the number of data packets that are flowing through said interface; and

means for identifying a potential defect of said means for moving data packets when said information indicates that said number of data packets is not increasing.

25. The system of claim 19 further comprising means for performing, in response to identifying a potential defect, a diagnostic test of said means for moving data packets.

26. The system of claim 19 further comprising means for switching to a redundant network routing device in response to identifying a potential defect.

27. The system of claim 26 wherein there is a limit to the number of times said switching can occur.

28. A system comprising:

a network routing device comprising a plurality of devices comprising a data path for moving data packets on said network routing device, wherein said data packets are communicated to and from a network via an interface;

a controller coupled to said network routing devices; and

a memory unit coupled to said controller, said memory unit containing instructions that when executed implement a process for monitoring said network routing device and detecting a defective device in said plurality of devices, wherein said process is executed within said plurality of devices allowing a defect in said data path to be detected and localized.

29. The system of claim 28 wherein said process comprises:

inserting a loop-back packet into a channel, wherein the destination specified for said loop-back packet is the same as the source of said loop-back packet causing said loop-back packet to travel from said source and back to said source through said devices on said network routing device; and

detecting whether said loop-back packet is received back at said source.

30. The system of claim 29 wherein said channel is dedicated to carrying said loop-back packet.

31. The system of claim 29 wherein said process further comprises:

inserting into said channel a plurality of loop-back packets at periodic intervals; and

identifying a potential defect of a device on said network routing device when the difference between the number of loop-back packets inserted and the number of loop-back packets received at said source exceeds a threshold.

32. The system of claim 31 wherein said process further comprises, in response to said identifying of said potential defect, determining whether said data packets are flowing through said interface.

33. The system of claim 28 wherein said process comprises:

accessing information that indicates the number of data packets that are flowing through said interface; and

identifying a potential defect of a device on said network routing device when said information indicates that said number of data packets is not increasing.

34. The system of claim 28 wherein said process further comprises, in response to identifying a potential defect, performing a diagnostic test of said devices on said network routing device.

35. The system of claim 28 wherein said process further comprises switching from said network routing device to another network routing device in response to identifying a potential defect.

36. The system of claim 35 wherein there is a limit to the number of times said switching can occur.