# US 2014/0207968 A1 · Server Load Balancer Traffic Steering > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0207968 A1 - Document ID: US20140207968A1 - Status: Published application - Kind: A1 - Application number: 13/748,072 - Filed: 2013-01-23 - Published: 2014-07-24 - Earliest claimed: 2013-01-23 - Assignees: Cisco Technology, Inc. - Applicants: Cisco Technology, Inc. - Inventors: Surendra M. Kumar; Nagaraj A. Bagepalli; Wei-Chun Chao - Web page: https://patentgrep.com/patent/US20140207968A1 ## CPC - H04L 45/38: {Flow based routing} - H04L 45/64: using an overlay routing layer - H04L 47/125: by balancing the load, e.g. traffic engineering - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract A network switch comprises a load balancer steering mechanism configured to receive a service request received from a load balancer and forward the service request to a first server in a load-balanced server cluster. The service request was initiated by a client and transmitted to the load balancer. The network switch is configured to receive return traffic transmitted by the first server, and to automatically steer the return traffic to the load balancer. ## Claims ### Claim 1 A method comprising: receiving, at a network switch, a service request forwarded from a load balancer on an overlay network, wherein the service request was initiated by a client; forwarding the service request to a first server in a load-balanced server cluster; receiving, at the network switch, a server traffic flow transmitted by a server in the load-balanced server cluster; and automatically steering the server traffic flow to the load balancer on the overlay network. ### Claim 2 (depends on 1) The method of claim 1, wherein automatically steering the server traffic flow to the load balancer comprises: determining, on a per-flow basis, whether to steer the server traffic flow to the load balancer ### Claim 3 (depends on 1) The method of claim 1, wherein automatically steering the server traffic flow to the load balancer comprises: steering all packets received on certain ports linked to the load-balanced server cluster to the load balancer. ### Claim 4 (depends on 1) The method of claim 1, wherein automatically steering the server traffic flow to the load balancer further comprises: encapsulating packets of the server traffic flow with an overlay header. ### Claim 5 (depends on 1) The method of claim 1, wherein packets in the service request received at the network switch are encapsulated with an overlay header to include metadata, and further comprising: decapsulating the packets in the service request; extracting the metadata from the overlay header; and processing the packets in the service request based on the metadata. ### Claim 6 (depends on 5) The method of claim 5, further comprising: determining, on a per-flow basis, if forwarding of the packets in the server request is permitted. ### Claim 7 (depends on 1) The method of claim 1, wherein the load balancer is configured to determine if the server traffic flow is return traffic, and further comprising: receiving, at the network switch, the server traffic flow back from the load balancer on the overlay network along with an offload indication signaling that the server traffic flow should be offloaded from the load balancer; and in response to the offload indication, configuring network switch such that future server traffic associated with the server traffic flow bypasses the load balancer. ### Claim 8 (depends on 1) The method of claim 1, further comprising determining, at the load balancer, that the server traffic flow is return traffic; and forwarding the server traffic flow to a client. ### Claim 9 (depends on 1) The method of claim 1, further comprising transmitting, at the load balancer, the service request to the switch on the overlay network without performing source network address translation on packets in the service request. ### Claim 10 An apparatus comprising: a plurality of network ports; a memory; and a processor configured to: receive, a service request forwarded from a load balancer on an overlay network, wherein the service request was initiated by a client; forward the service request to a first server in a load-balanced server cluster; receive a server traffic flow transmitted by a server in the load-balanced server cluster; and automatically steer the server traffic flow to the load balancer on the overlay network. ### Claim 11 (depends on 10) The apparatus of claim 10, wherein to automatically steer the server traffic flow to the load balancer, the processor is configured to: determine, on a per-flow basis, whether to steer the server traffic flow to the load balancer ### Claim 12 (depends on 10) The apparatus of claim 10, wherein to automatically steer the server traffic flow to the load balancer, the processor is configured to: steering all packets received on certain ports linked to the load-balanced server cluster to the load balancer. ### Claim 13 (depends on 10) The apparatus of claim 10, wherein to automatically steer the server traffic flow to the load balancer, the processor is configured to: encapsulating packets of the server traffic flow with an overlay header. ### Claim 14 (depends on 10) The apparatus of claim 10, wherein packets in the received service request are encapsulated with an overlay header to include metadata, and wherein the processor is configured to: decapsulate the packets in the service request; extract the metadata from the overlay header; and process the packets in the service request based on the metadata. ### Claim 15 (depends on 14) The apparatus of claim 14, wherein the processor is configured to: determine, on a per-flow basis, if forwarding of the packets in the server request is permitted. ### Claim 16 (depends on 10) The apparatus of claim 10, wherein the load balancer is configured to determine if the server traffic flow is return traffic, and wherein the processor is configured to: receive the server traffic flow back from the load balancer on the overlay network along with an offload indication signaling that the server traffic flow should be offloaded from the load balancer; and in response to the offload indication, bypassing the load balancer when future server traffic associated with the server traffic flow is received. ### Claim 17 One or more computer readable storage media encoded with software comprising computer executable instructions and when the software is executed operable to: receive, at a network switch, a service request forwarded from a load balancer on an overlay network, wherein the service request was initiated by a client; forward the service request to a first server in a load-balanced server cluster; receiving, at the network switch, a server traffic flow transmitted by a server in the load-balanced server cluster; and automatically steer the server traffic flow to the load balancer on the overlay network. ### Claim 18 (depends on 17) The computer readable storage media of claim 17, wherein the instructions operable to automatically steer the server traffic flow to the load balancer comprise instructions operable to: determine, on a per-flow basis, whether to steer the server traffic flow to the load balancer ### Claim 19 (depends on 17) The computer readable storage media of claim 17, wherein the instructions operable to automatically steer the server traffic flow to the load balancer comprise instructions operable to: steer all packets received on certain ports linked to the load-balanced server cluster to the load balancer. ### Claim 20 (depends on 17) The computer readable storage media of claim 17, wherein the instructions operable to automatically steer the server traffic flow to the load balancer comprise instructions operable to: encapsulate packets of the server traffic flow with an overlay header. ### Claim 21 (depends on 17) The computer readable storage media of claim 17, wherein packets in the service request received at the network switch are encapsulated with an overlay header to include metadata, and further comprising instructions operable to: decapsulate the packets in the service request; extract the metadata from the overlay header; and process the packets in the service request based on the metadata. ### Claim 22 (depends on 21) The computer readable storage media of claim 21, further comprising instructions operable to: determine, on a per-flow basis, if forwarding of the packets in the server request is permitted. ### Claim 23 (depends on 17) The computer readable storage media of claim 17, wherein the load balancer is configured to determine if the server traffic flow is return traffic, and further comprising instructions operable to: receive, at the network switch, the server traffic flow back from the load balancer on the overlay network along with an offload indication signaling that the server traffic flow should be offloaded from the load balancer; and in response to the offload indication, configure network switch such that future server traffic associated with the server traffic flow bypasses the load balancer.