INTER-POD TRAFFIC REDIRECTION AND HANDLING IN A MULTI-POD NETWORK ENVIRONMENT

• US 20160277355A1
• Filed: 03/18/2015
• Published: 09/22/2016
• Est. Priority Date: 03/18/2015
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Shetty, Nikhil Gopinath, Rathi, Ravindra Nandalal, Song, Jialin, Gaggara, Siva
• Granted Patent: US 9,967,231 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04L 12/4633 Interconnection of networks using encapsulation techniques, e.g. tunneling
• CPC Class Codes: H04L 45/72 Routing based on the source address
• CPC Class Codes: H04L 45/745 Address table lookup; Address filtering
• CPC Class Codes: H04L 49/3009 Header conversion, routing tables or routing tags
• CPC Class Codes: H04L 61/2514 between local and global IP addresses
• CPC Class Codes: H04L 61/2592 using tunnelling or encapsulation

Abstract

An example method for to inter-pod traffic redirection and handling in a multi-pod network environment is provided and includes receiving a packet with an overlay header outgoing from a first pod, identifying the packet as redirected based on a source address in the overlay header indicating a second pod and a destination address in the overlay header indicating a third pod, the first pod being distinct from the second pod and the third pod, setting a redirection bit in the overlay header tagging the packet as redirected, and transmitting the packet to the third pod.

Claims

1. A method executed by a hardware translator in a multi-pod network environment, comprising:

receiving, at the translator, a packet with an overlay header outgoing from a first pod;

identifying the packet, by the translator, as redirected based on a source address in the overlay header indicating a second pod and a destination address in the overlay header indicating a third pod, the first pod being distinct from the second pod and the third pod;

setting, by the translator, a redirection bit in the overlay header tagging the packet as redirected; and

transmitting the packet, by the translator, to the third pod.

2. The method of claim 1, further comprising:

rewriting the source address to an address of the first pod.

3. The method of claim 1, further comprising:

receiving a second packet with a second overlay header incoming into the first pod;

identifying the second packet as redirected based on a value of the redirection bit in the second overlay header;

rewriting the source address and the destination address in the second overlay header to a local address in the first pod;

stripping the redirection bit from the overlay header; and

transmitting the second packet to the local address in the first pod.

4. The method of claim 3, wherein a destination switch flushes a data path of the second packet and does not learn the source address in the second overlay header based on the source address and the destination address in the second overlay header.

5. The method of claim 4, wherein the destination switch determines a corrected source address by a lookup of a local endpoint repository.

6. The method of claim 1, further comprising:

receiving a second packet with a second overlay header outgoing from the first pod;

identifying the second packet as not redirected based on a source address in the second overlay header indicating a local address in the first pod and the destination address in the third overlay header indicating the third pod;

clearing the redirection bit indicating that the packet is not redirected; and

transmitting the packet to the third pod.

7. The method of claim 1, further comprising:

receiving a second packet with a second overlay header incoming into the first pod;

identifying the second packet as not redirected based on a value of the redirection bit in the second overlay header;

rewriting the destination address in the second overlay header to a local address in the first pod;

stripping the redirection bit from the overlay header; and

transmitting the second packet to the local address in the first pod.

8. The method of claim 7, wherein the redirection bit is cleared to zero to tag the packet as not redirected.

9. The method of claim 1, wherein the redirection bit is set to one to tag the packet as redirected.

10. The method of claim 1, wherein each pod comprises a fabric including a plurality of spine switches interconnected to leaf switches, wherein the leaf switches are connected to endpoints that generate or terminate packets in a data plane.

11. Non-transitory tangible media that includes instructions for execution by a processor of a translator in a multi-pod network environment to perform operations comprising:

receiving, at the translator, a packet with an overlay header outgoing from a first pod;

identifying the packet, by the translator, as redirected based on a source address in the overlay header indicating a second pod and a destination address in the overlay header indicating a third pod, the first pod being distinct from the second pod and the third pod;

setting, by the translator, a redirection bit in the overlay header tagging the packet as redirected; and

transmitting the packet, by the translator, to the third pod.

12. The media of claim 11, wherein the operations further comprise:

receiving a second packet with a second overlay header incoming into the first pod;

identifying the second packet as redirected based on a value of the redirection bit in the second overlay header;

rewriting the source address and the destination address in the second overlay header to a local address in the first pod;

stripping the redirection bit from the overlay header; and

transmitting the second packet to the local address in the first pod.

13. The media of claim 12, wherein a destination switch flushes a data path of the second packet and does not learn the source address in the second overlay header based on the source address and the destination address in the second overlay header.

14. The media of claim 11, wherein the operations further comprise:

receiving a second packet with a second overlay header outgoing from the first pod;

identifying the second packet as not redirected based on a source address in the second overlay header indicating a local address in the first pod and the destination address in the third overlay header indicating the third pod;

clearing the redirection bit indicating that the packet is not redirected; and

transmitting the packet to the third pod.

15. The media of claim 11, wherein the operations further comprise:

receiving a second packet with a second overlay header incoming into the first pod;

identifying the second packet as not redirected based on a value of the redirection bit in the second overlay header;

rewriting the destination address in the second overlay header to a local address in the first pod;

stripping the redirection bit from the overlay header; and

transmitting the second packet to the local address in the first pod.

16. An apparatus in a multi-pod network environment, comprising:

a memory element for storing data; and

a processor, wherein the processor executes instructions associated with the data, wherein the processor and the memory element cooperate, such that the apparatus is configured for;

receiving a packet with an overlay header outgoing from a first pod;

identifying the packet as redirected based on a source address in the overlay header indicating a second pod and a destination address in the overlay header indicating a third pod, the first pod being distinct from the second pod and the third pod;

setting a redirection bit in the overlay header tagging the packet as redirected; and

transmitting the packet to the third pod.

17. The apparatus of claim 16, further configured for:

receiving a second packet with a second overlay header incoming into the first pod;

identifying the second packet as redirected based on a value of the redirection bit in the second overlay header;

rewriting the source address and the destination address in the second overlay header to a local address in the first pod;

stripping the redirection bit from the overlay header; and

transmitting the second packet to the local address in the first pod.

18. The apparatus of claim 17, wherein a destination switch flushes a data path of the second packet and does not learn the source address in the second overlay header based on the source address and the destination address in the second overlay header.

19. The apparatus of claim 16, further configured for:

receiving a second packet with a second overlay header outgoing from the first pod;

identifying the second packet as not redirected based on a source address in the second overlay header indicating a local address in the first pod and the destination address in the third overlay header indicating the third pod;

clearing the redirection bit indicating that the packet is not redirected; and

transmitting the packet to the third pod.

20. The apparatus of claim 16, further configured for:

receiving a second packet with a second overlay header incoming into the first pod;

identifying the second packet as not redirected based on a value of the redirection bit in the second overlay header;

rewriting the destination address in the second overlay header to a local address in the first pod;

stripping the redirection bit from the overlay header; and

transmitting the second packet to the local address in the first pod.