Address resolution suppression for data center interconnect

• US 9,548,959 B2
• Filed: 03/23/2012
• Issued: 01/17/2017
• Est. Priority Date: 03/23/2012
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Boutros, Sami, Salam, Samer, Sajassi, Ali, Filsfils, Clarence
• Primary Examiner(s): Hussain, Tauqir
• Assistant Examiner(s): Keller, Michael A
• Application Number:
  US13/428,436
• Publication Number:
  US 20130254359A1
• Time in Patent Office: 1,761 Days
• Field of Search: 709220-229
• US Class Current: 1/1
• CPC Class Codes: H04L 61/103 across network layers, e.g. resolution of network layer into physical layer addresses or address resolution protocol [ARP]
• CPC Class Codes: H04L 61/58 Caching of addresses or names

Abstract

An example method is provided that includes determining whether an address resolution protocol reply from a local machine has been received at an edge node; updating a local cache based on the reply from the local machine; and sending the reply to a plurality of edge nodes through a data plane of a data center interconnect. In more specific implementations, the method can include determining whether an address resolution protocol request has been received from the local machine. The method could also include updating a local machine cache based on the request. In certain implementations, the method can include determining whether the request is targeting the local machine; and dropping the request if the request is targeting the local machine. The method could also include sending the request through the data center interconnect if the request is not targeting the local machine.

Claims

1. A method to be performed by an edge node, wherein the edge node communicatively connects a data center to a data center interconnect, the method comprising:

building a cache as address resolution protocol (ARP) messages are received in a network environment, wherein the cache includes information about local machines not located over the data center interconnect and remote machines located over the data center interconnect;

receiving an ARP reply from a local machine associated with the data center;

updating the cache based on the ARP reply from the local machine, wherein a local machine identifier for the local machine is stored in the cache when the local machine has not already been identified in the cache;

sending the ARP reply to a plurality of edge nodes through a data plane of the data center interconnect, wherein each of the plurality of edge nodes communicatively connects a respective data center to the data center interconnect;

receiving an ARP reply from a remote machine in the data plane;

when the ARP reply is associated with an ARP request from one of the local machines associated with the data center, sending the ARP reply to the one of the local machines; and

when the ARP reply is not associated with an ARP request from one of the local machines associated with the data center, dropping the ARP reply; and

snooping in the data plane for the ARP messages in a multicast tunnel.

2. The method of claim 1, further comprising:

receiving an ARP request from the local machine; and

determining whether a target machine identified in the ARP request is a local machine associated with the data center.

3. The method of claim 2, further comprising:

updating the cache based on the ARP request from the local machine, wherein a local machine identifier for the local machine is stored in the cache when the local machine has not already been identified in the cache.

4. The method of claim 2, further comprising:

when the cache includes a local machine identifier for the target machine, dropping the ARP request.

5. The method of claim 2, further comprising:

when the target machine is not a local machine, sending the ARP request to the plurality of edge nodes through the data plane of the data center interconnect.

6. The method of claim 2, further comprising:

when the cache does not include a local machine identifier for the target machine, determining whether the cache includes an address binding for the target machine; and

when the cache includes an address binding for the target machine, sending an ARP reply message to the local machine that includes the address binding.

7. The method of claim 6, further comprising:

when the cache does not include an address binding for the target machine, sending the ARP request to the plurality of edge nodes through the data plane of the data center interconnect.

8. The method of claim 1, further comprising:

receiving an ARP request from a remote machine in the data plane;

updating the cache based on the ARP request from the remote machine, wherein the edge node stores an address binding for the remote machine in the cache when the remote machine has not already been identified in the cache; and

sending the ARP request to at least one local machine associated with the data center.

9. The method of claim 1, further comprising:

updating the cache based on the ARP reply from the remote machine, wherein the edge node stores an address binding for the remote machine in the cache when the remote machine has not already been identified in the cache.

10. The method of claim 1, further comprising altering a delivery technique for sending the ARP reply from unicast to a multicast tunnel or a broadcast tunnel.

11. An edge node that communicatively connects a data center with a data center interconnect, the edge node comprising:

a memory for storing data, wherein the memory includes a cache for storing information about local machines not located over the data center interconnect and remote machines located over the data center interconnect; and

a processor operable to execute instructions associated with the data, wherein the processor and the memory cooperate such that the edge node is configured for;

building the cache as address resolution protocol (ARP) messages are received in a network environment;

receiving an ARP reply from a local machine associated with the data center;

updating the cache based on the ARP reply from the local machine, wherein a local machine identifier for the local machine is stored in the cache when the local machine has not already been identified in the cache; and

sending the ARP reply to a plurality of edge nodes through a data plane of the data center interconnect, wherein each of the plurality of edge nodes communicatively connects a respective data center to the data center interconnect;

receiving an ARP reply from a remote machine in the data plane;

when the ARP reply is associated with an ARP request from one of the local machines associated with the data center, sending the ARP reply to the one of the local machines; and

when the ARP reply is not associated with an ARP request from one of the local machines associated with the data center, dropping the ARP reply; and

snooping in the data plane for the ARP messages in a multicast tunnel.

12. The edge node of claim 11, further configured for:

determining whether an ARP request has been received from the local machine;

updating the cache based on the ARP request from the local machine, wherein a local machine identifier for the local machine is stored in the cache when the local machine has not already been identified in the cache; and

determining whether a target machine identified in the ARP request is a local machine associated with the data center.

13. The edge node of claim 12, further configured for:

when the cache includes a local machine identifier for the target machine, dropping the ARP request.

14. The edge node of claim 13, further configured for:

when the target machine is not a local machine, sending the ARP request to the plurality of edge nodes through the data plane of the data center interconnect.

15. The edge node of claim 12, further configured for:

when the cache does not include a local machine identifier for the target machine, determining whether the cache includes an address binding for the target machine; and

when the cache includes an address binding for the target machine, sending an ARP reply message to the local machine that includes the address binding.

16. One or more non-transitory media encoded with logic that includes code for execution, and when executed by one or more processors of an edge node configured to communicatively connect a data center with a data center interconnect, is operable to perform operations comprising:

building a cache as address resolution protocol (ARP) messages are received in a network environment, wherein the cache includes information about local machines not located over the data center interconnect and remote machines located over the data center interconnect;

receiving an ARP reply from a local machine associated with the data center;

updating the cache based on the ARP reply from the local machine, wherein a local machine identifier for the local machine is stored in the cache when the local machine has not already been identified in the cache; and

sending the ARP reply to a plurality of edge nodes through a data plane of the data center interconnect, wherein each of the plurality of edge nodes communicatively connects a respective data center to the data center interconnect;

receiving an ARP reply from a remote machine in the data plane;

when the ARP reply is associated with an ARP request from one of the local machines associated with the data center, sending the ARP reply to the one of the local machines; and

when the ARP reply is not associated with an ARP request from one of the local machines associated with the data center, dropping the ARP reply; and

snooping in the data plane for the ARP messages in a multicast tunnel.

17. The non-transitory media of claim 16, the operations further comprising:

receiving an ARP request from the local machine; and

determining whether a target machine identified in the ARP request is a local machine associated with the data center.

18. The non-transitory media of claim 17, the operations further comprising:

updating the cache based on the ARP request from the local machine, wherein a local machine identifier for the local machine is stored in the cache when the local machine has not already been identified in the cache.

19. The non-transitory media of claim 17, the operations further comprising:

when the cache includes a local machine identifier for the target machine, dropping the ARP request.