Method and system for overlay routing with vxlan

Abstract

In general, embodiments of the invention relate to routing packets between hosts or virtual machines in different layer 2 domains. More specifically, embodiments of the invention relate to using overlay routing mechanisms in an Internet Protocol (IP) fabric to enable communication between hosts or virtual machines in different layer 2 domains to communication. The overlay routing mechanisms may include direct routing, indirect routing, naked routing, or a combination thereof (e.g., hybrid routing).

1 .- 20 . (canceled) 
     
     
         21 . A system for routing a first packet comprising:
 a first network device, wherein the first network device is configured to receive a first encapsulated packet and rewrite a source media access control (MAC) frame to create a rewritten source MAC frame,   wherein said first encapsulated packet is an encapsulation of the first packet comprising the source MAC frame,   wherein said source MAC frame comprises: a payload, the first source MAC address, a first destination MAC address, a first source Internet Protocol (IP) address, and a first destination IP address,   said first source MAC address is associated with the first VXLAN, and said first destination MAC address is associated with a virtual address resolution protocol (VARP) virtual tunnel end point (VTEP),   wherein said rewritten source MAC frame replaces the first source MAC address with a MAC address associated with the VARP VTEP, and replaces the first destination MAC address with a MAC address associated with a second Virtual Extensible Local Area Network (VXLAN),   wherein a first server is associated with the first VXLAN and the second VXLAN,   wherein the first VXLAN and the second VXLAN are distinct,   wherein the first server is configured to receive the first packet and encapsulate the first packet in a first VXLAN frame to create the first encapsulated packet,   wherein said first packet comprises: a source media access control (MAC) frame,   wherein said first source IP address is associated with the first VXLAN and said first destination IP address is associated with the second VXLAN,   wherein said first VXLAN frame comprises a second destination IP address,   wherein the second destination IP address is a VARP VTEP IP address, and   wherein the first server and the first network device are configured to communicate with a second server associated with the first VXLAN and the second VXLAN.   
     
     
         22 . The system of  claim 21 , wherein the first network device is a Top of Rack (ToR) switch. 
     
     
         23 . The system of  claim 21 , wherein the first network device is further configured to decapsulate the first encapsulated packet to reveal the first packet before rewriting the source MAC frame. 
     
     
         24 . The system of  claim 21 , wherein the first network device is further configured to re-encapsulate the rewritten source MAC frame in a second VXLAN frame to create a re-encapsulated packet. 
     
     
         25 . The system of  claim 24 , wherein the second VXLAN frame allows the re-encapsulated packet to be routed to the second server on the second VXLAN. 
     
     
         26 . The system of  claim 21 , wherein the first network device is configured to route the first packet using a direct overlay. 
     
     
         27 . The system of  claim 21 , wherein the first server comprises a first routing table portion for an underlay network and a second routing table portion for an overlay network, and wherein the second routing table portion comprises information relating an IP address to a layer- 2  domain. 
     
     
         28 . The system of  claim 21 , further comprising a spine tier comprising at least one spine switch. 
     
     
         29 . The system of  claim 21 , further comprising a leaf tier comprising the first network device. 
     
     
         30 . The system of  claim 29 , wherein the leaf tier further comprises a second network device for connecting the first network device to the second server. 
     
     
         31 . The system of  claim 30 , wherein the second network device is a ToR switch. 
     
     
         32 . A system for routing a first packet comprising:
 a first server associated with a first Virtual Extensible Local Area Network (VXLAN) and a second VXLAN, wherein the first VXLAN and the second VXLAN are distinct;   the first server configured to receive a first packet and encapsulate the first packet in a first VXLAN frame to create a first encapsulated packet,   said first packet comprising: a source media access control (MAC) frame,   said source MAC frame comprising: a payload, a first source MAC address, a first destination MAC address, a first source Internet Protocol (IP) address, and a first destination IP address, said first source MAC address associated with the first VXLAN, and said first destination MAC address associated with a virtual address resolution protocol (VARP) virtual tunnel end point (VTEP),   said first source IP address associated with the first VXLAN and said first destination IP address associated with the second VXLAN,   
       said first VXLAN frame comprising a second destination IP address, wherein the second destination IP address is a VARP VTEP IP address; and
 a first network device configured to receive the first encapsulated packet, rewrite the source MAC frame to create a rewritten source MAC frame, and re-encapsulate the first packet in a second VXLAN frame to create a re-encapsulated packet, 
 said rewritten source MAC frame replacing the first source MAC address with a MAC address associated with a second network device, and replacing the first destination MAC address with a MAC address associated with the VARP VTEP; 
 the second network device configured to receive the re-encapsulated packet, rewrite the source MAC frame to create a second rewritten source MAC frame, and re-encapsulate the packet in a third VXLAN frame, 
 said second rewritten source MAC frame replacing the first source MAC address with a MAC address associated with the VARP VTEP, and replacing the first destination MAC address with a MAC address associated with the second VXLAN, 
 wherein the first server and the first network device are configured to communicate with a second server associated with the first VXLAN and the second VXLAN. 
 
     
     
         33 . The system of  claim 32 , wherein the first network device and the second network device are configured to route the first packet using an indirect overlay. 
     
     
         34 . The system of  claim 33 , wherein the first network device and the second network device are configured to route the first packet on a third VXLAN therebetween. 
     
     
         35 . The system of  claim 32 , wherein the first network device is a first Top of Rack (ToR) switch, and the second network device is a second ToR switch. 
     
     
         36 . The system of  claim 32 , wherein the first network device and the second network device are configured to route the first packet using a naked overlay. 
     
     
         37 . The system of  claim 36 , wherein the first network device and the second network device are configured to route the first packet therebetween not using a VXLAN protocol. 
     
     
         38 . A first network device comprising:
 at least one processor; and   a non-transitory computer-readable medium storing computer-executable instructions to cause the at least one processor to perform a method for routing a first packet from a first layer- 2  domain to a second layer- 2  domain, the method comprising:
 receiving the first packet addressed to the first network device, wherein the first packet comprises a first VXLAN frame encapsulating a source MAC frame to form a first encapsulated packet, 
 decapsulating the first encapsulated packet to obtain the source MAC frame; 
 rewriting the source MAC frame by changing a destination address from a VARP VTEP MAC address to a second layer- 2  domain MAC address, and changing a source address from a first layer- 2  domain MAC address to the VARP VTEP MAC address; 
 generating a re-encapsulated packet comprising the rewritten source MAC frame and a second VXLAN frame; and 
 routing the re-encapsulated packet towards the destination address in the second layer- 2  domain, 
 wherein the first network device maintains a plurality of VARP VTEP MAC addresses, each VARP VTEP MAC address being associated with a different layer- 2  domain. 
   
     
     
         39 . The first network device of  claim 38 , wherein the first network device is configured to route the first packet using a direct overlay. 
     
     
         40 . The first network device of  claim 38 , wherein the first network device is a ToR switch.