Redundant application network appliances using a low latency lossless interconnect link

• US 7,895,463 B2
• Filed: 04/11/2008
• Issued: 02/22/2011
• Est. Priority Date: 08/28/2007
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Patra, Abhijit, Prabhu, Kirti, Thakar, Anant, Bagepalli, Nagaraj, Gandhi, Prashant
• Primary Examiner(s): Baderman; Scott T
• Assistant Examiner(s): Leibovich; Yair
• Application Number:
  US12/101,865
• Publication Number:
  US 20090063893A1
• Time in Patent Office: 1,047 Days
• Field of Search: 714/4
• US Class Current: 714/4.1
• CPC Class Codes: H04L 47/20 Traffic policing
• CPC Class Codes: H04L 63/02 for separating internal from external traffic, e.g. firewalls
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: H04L 63/166 at the transport layer
• CPC Class Codes: H04L 63/205 involving negotiation or determination of the one or more network security mechanisms to be used, e.g. by negotiation between the client and the server or between peers or by selection according to the capabilities of the entities involved negotiation of communication capabilities H04L69/24
• CPC Class Codes: H04L 69/16 Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]
• CPC Class Codes: H04L 69/161 Implementation details of TCP/IP or UDP/IP stack architecture; Specification of modified or new header fields
• CPC Class Codes: H04L 69/321 Interlayer communication protocols or service data unit [SDU] definitions; Interfaces between layers
• CPC Class Codes: H04L 9/3242 involving keyed hash functions, e.g. message authentication codes [MACs], CBC-MAC or HMAC
• CPC Class Codes: Y10T 70/5827 Axially movable clutch

Abstract

Redundant application network appliances using a low latency lossless interconnect link are described herein. According to one embodiment, in response to receiving at a first network element a packet of a network transaction from a client over a first network for accessing a server of a datacenter, a layer 2 network process is performed on the packet and a data stream is generated. The data stream is then replicated to a second network element via a layer 2 interconnect link to enable the second network element to perform higher layer processes on the data stream to obtain connection states of the network transaction. In response to a failure of the first network element, the second network element is configured to take over processes of the network transaction from the first network element using the obtained connection states without user interaction of the client. Other methods and apparatuses are also described.

Claims

1. A method comprising:

in response to receiving at a first network element a packet of a network transaction from a client over a first network for accessing a server of a datacenter having a plurality of servers over a second network, performing a layer 2 network process on the packet and generating a data stream within the first network element;

performing a layer-3 handshaking with a second network element via a lossless interconnect link coupling the first network element and the second network element;

replicating the data stream to the second network element via the lossless interconnect link to synchronize layer-4 states between the first network element and the second network element and to enable the second network element to perform higher layer processes on the data stream with respect to the network transaction to obtain connection states of the network transaction;

wherein the second network element is configured to operate as a redundant peer to the first network element; and

wherein in response to a failure of the first network element, the second network element is configured to take over processes of the network transaction from the first network element using the obtained connection states without user interaction of the client.

2. The method of claim 1, wherein performing comprises performing the layer-3 handshaking with the second network element via the lossless interconnect link that is implemented using one of a remote direct memory access (RDMA) compatible technology, an InfiniBand compatible technology and a lossless interconnect.

3. The method of claim 1, further comprising:

performing layer 5-7 processes on the packet within the first network element to obtain layer 5-7 connection states of the network transaction;

storing the layer 5-7 connection states in a first memory of the first network element; and

synchronizing the layer 5-7 connection states with the second network element by synchronizing at least a portion of content of the first memory of the first network element and at least a portion of content of a second memory of a second network element via a predetermined low latency lossless interconnect link.

4. The method of claim 3, wherein synchronizing comprises synchronizing the first memory of the first network element and the second memory of the second network element via one of a remote direct memory access (RDMA) compatible technology and a lossless fabric.

5. The method of claim 4, further comprising exposing at least a portion of the first memory of the first network element to the second network element such that the second network element configured to read content of the portion of first memory of the first network that is exposed to obtain the layer 5-7 connection states.

6. The method of claim 5, wherein exposing comprises exposing the portion of the first memory of the first network element such that the portion of the first memory is read by the second network element via an RDMA channel without involving significant processing power from the first network element.

7. The method of claim 5, further comprising directly accessing at the second network element the portion of the first memory that is exposed via an RDMA channel bypassing a transport control protocol (TCP) network stack of the first network element.

8. The method of claim 1, further comprising configuring the second network element to monitor a health of the first network element via a dedicated monitoring channel over the lossless interconnect link to determine whether the first network element is operating properly, and if it is determined that the first network element fails to operate properly, configuring the second network element to transparently take over the network processes of the network transaction using the obtained connection states without acknowledgment from the client.

9. A machine-readable storage medium having instructions stored therein, which when executed by a processor, cause the processor to:

in response to receiving at a first network element a packet of a network transaction from a client over a first network for accessing a server of a datacenter having a plurality of servers over a second network, perform a layer 2 network process on the packet and generating a data stream within the first network element;

perform a layer-3 handshaking with a second network element via a lossless interconnect link coupling the first network element and the second network element; and

replicate the data stream to the second network element via the lossless interconnect link to synchronize layer-4 states between the first network element and the second network element and to enable the second network element to perform higher layer processes on the data stream with respect to the network transaction to obtain connection states of the network transaction, wherein the second network element is configured to operate as a redundant peer to the first network element, and wherein in response to a failure of the first network element, the second network element is configured to take over processes of the network transaction from the first network element using the obtained connection states without user interaction of the client.

10. The machine-readable storage medium of claim 9, wherein the instructions that cause the processor to perform the layer-3 handshaking with the second network element comprise instructions that cause the processor to perform the layer-3 handshaking with the second network element via the lossless interconnect link is implemented using one of a remote direct memory access (RDMA) and capable compatible technology, an InfiniBand compatible technology.

11. The machine-readable storage medium of claim 9, further comprising instructions that cause the processor to:

perform layer 5-7 processes on the packet within the first network element to obtain layer 5-7 connection states of the network transaction;

store layer 5-7 connection states in a first memory of the first network element; and

synchronize the layer 5-7 connection states with the second network element by synchronizing at least a portion of content of the first memory of the first network element and at least a portion of content of a second memory of a second network element via a predetermined low latency lossless interconnect link.

12. The machine-readable storage medium of claim 11, wherein the instructions that cause the processor to synchronize the layer 5-7 connection states comprise instructions that cause the processor to synchronize the first memory of the first network element and the second memory of the second network element via one of a remote direct memory access (RDMA) compatible technology and a lossless fabric.

13. The machine-readable storage medium of claim 12, further comprising instructions that cause the processor to expose at least a portion of the first memory of the first network element to the second network element such that the second network element is able to read content of the a portion of first memory of the first network that is exposed to obtain the layer 5-7 connection states.

14. The machine-readable storage medium of claim 13, wherein the instructions that cause the processor to expose at least a portion of the first memory comprise instructions that cause the processor to expose the portion of the first memory of the first network element such that the portion of the first memory is read by the second network element via an RDMA channel without involving significant processing power from the first network element.

15. The machine-readable storage medium of claim 13, further comprising instructions that cause the processor to directly access at the second network element the portion of the first memory that is exposed via an RDMA channel bypassing a transport control protocol (TCP) network stack of the first network element.

16. The machine-readable storage medium of claim 9, further comprising instructions that cause the processor to configure the second network element to monitor a health of the first network element via a dedicated monitoring channel over the lossless interconnect link to determine whether the first network element is operating properly, and if it is determined that the first network element fails to operate properly, configure the second network element to transparently take over the network processes of the network transaction using the obtained connection states without acknowledgment from the client.

17. An apparatus, comprising:

at least a first network interface coupled to a switch fabric;

a processor configured to be coupled to the first network interface and configured to perform network service operations comprising;

in response to receiving a packet of a network transaction at the first network interface from a client over a first network for accessing a server of a datacenter having a plurality of servers over a second network, executing a layer 2 process on the packet to generate a data stream;

executing a layer 3 handshaking procedure over a lossless interconnect coupled with a second network apparatus;

wherein replicating the data stream and sending the data stream to the second network apparatus as a redundant peer via the lossless interconnect link to synchronize layer-4 states with the redundant peer, enable the redundant peer to perform higher layer processes on the data stream to obtain connection states of the network transaction; and

in response to a failure, configuring the redundant peer to take over network processes of the network transaction using the obtained connection states without user interaction from the client.

18. The apparatus of claim 17, wherein the processor is configured to execute the layer 3 handshaking over the lossless interconnect link using one of a remote direct memory access (RDMA) compatible technology and an InfiniBand compatible technology.

19. The apparatus of claim 17, wherein the processor is further configured to execute network service operations comprising:

layer 5-7 processing on the packet to obtain layer 5-7 connection states of the network transaction;

storing the layer 5-7 connection states in a first memory; and

synchronizing the layer 5-7 connection states with the redundant peer by synchronizing at least a portion of content of the first memory and at least a portion of content of a second memory of the redundant peer via the low latency lossless interconnect link.

20. The apparatus of claim 19, wherein the processor is configured to synchronize the first memory and the second memory of the redundant peer via one of a remote direct memory access (RDMA) compatible technology and an InfiniBand compatible technology.

21. A system comprising the apparatus of claim 20, wherein a processor of the redundant peer is configured to read content of at least a portion of the first memory that is exposed to the redundant peer to obtain the layer 5-7 connection states.

22. The system of claim 21, wherein the processor of the redundant peer is configured to read the first memory via an RDMA channel without involving significant processing power from the network element.

23. The system of claim 21, wherein the processor of the redundant peer is configured to directly access the first memory that is exposed via an RDMA channel bypassing a transport control protocol (TCP) network stack of the network element.

24. A system comprising the apparatus of claim 17, wherein a processor of the redundant peer is configured monitor a health of the apparatus via a dedicated monitoring channel over the lossless interconnect link to determine whether the apparatus is operating properly, and wherein if it is determined that the apparatus fails to operate properly, the processor of the redundant peer is configured to transparently take over the network processes of the network transaction using the obtained connection states without acknowledgment from the client.