HANDLING NAT IN LOGICAL L3 ROUTING

• US 20130148542A1
• Filed: 02/01/2013
• Published: 06/13/2013
• Est. Priority Date: 08/17/2011
• Status: Active Grant

• Current Assignee: Nicira Incorporated (Broadcom, Inc.)
• Original Assignee: Nicira Incorporated (Broadcom, Inc.)
• Inventors: Zhang, Ronghua, Thakkar, Pankaj, Koponen, Teemu
• Granted Patent: US 9,350,696 B2
• Time in Patent Office: Days
• US Class Current: 370/254
• CPC Class Codes: H04L 41/0803 Configuration setting
• CPC Class Codes: H04L 45/04 Interdomain routing, e.g. hierarchical routing
• CPC Class Codes: H04L 45/54 Organization of routing tables
• CPC Class Codes: H04L 45/74 Address processing for routing
• CPC Class Codes: H04L 47/12 Avoiding congestion; Recovering from congestion
• CPC Class Codes: H04L 47/125 by balancing the load, e.g. traffic engineering
• 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 61/256 NAT traversal
• CPC Class Codes: H04L 61/2592 using tunnelling or encapsulation

Abstract

A non-transitory machine readable medium storing a program that configures first and second managed forwarding elements to perform logical L2 switching and L3 routing is described. The program generates a first set of flow entries for configuring the first managed forwarding element to perform (1) a first logical L2 processing for a first logical L2 domain, (2) a logical L3 processing, (3) a network address translation (NAT) processing on packets to be sent to the second managed forwarding element, and (4) a logical ingress L2 processing for a second logical L2 domain on the packets. The program generates a second set of flow entries for configuring the second managed forwarding element to perform a logical egress L2 processing for the second logical L2 domain on the packets.

Claims

1. A non-transitory machine readable medium storing a program which when executed by at least one processing unit configures first and second managed forwarding elements to perform logical L2 switching and L3 routing, the program comprising sets of instructions for:

generating a first set of flow entries for configuring the first managed forwarding element to perform (i) a first logical L2 processing for a first logical L2 domain, (ii) a logical L3 processing, (iii) a network address translation (NAT) processing on packets to be sent to the second managed forwarding element, and (iv) a logical ingress L2 processing for a second logical L2 domain on the packets; and

generating a second set of flow entries for configuring the second managed forwarding element to perform a logical egress L2 processing for the second logical L2 domain on the packets.

2. The machine readable medium of claim 1, wherein the NAT processing comprises

(i) source NAT operations for translating a source address of a packet into another address and

(ii) a destination NAT operations for translating a destination address of the packet into another address.

3. The machine readable medium of claim 2, wherein the source and destination addresses are IP addresses.

4. The machine readable medium of claim 2, wherein the first set of flow entries is further for configuring the first managed forwarding element to perform the destination NAT operations before performing the source NAT operations.

5. The machine readable medium of claim 1, wherein the first logical L2 processing comprises identifying a port of a logical forwarding element for the first logical L2 domain, the identified port corresponding to a logical router for the logical L3 processing.

6. The machine readable medium of claim 5, wherein the identified port has a MAC address corresponding to the logical router.

7. The machine readable medium of claim 1, wherein the logical L3 processing comprises identifying a port of a logical router, the port corresponding to the second logical L2 domain.

8. The machine readable medium of claim 7, wherein the identified port is associated with an IP address that corresponds to an IP subnet for the second logical L2 domain.

9. For a network controller for managing a network comprising managed forwarding elements, the method comprising:

configuring a managed forwarding element in a host as a second-level managed forwarding element;

configuring a router in the host, the router for performing network address translation (NAT) on a packet;

communicatively coupling the second-level managed forwarding element with the router in the host,

wherein the router routes the packet based on a translated address when the router receives the packet from a machine in a first logical domain that is sent to another machine in a second logical domain.

10. The method of claim 9, wherein the second-level managed forwarding element is facilitates communications between two edge forwarding elements, wherein the edge forwarding elements interfaces directly with sources and destinations of packets, wherein the second-level managed switching element does not directly interface with the sources and destinations of packets.

11. The method of claim 9, wherein configuring the router in the host comprises configuring the router in a namespace of the host.

12. The method of claim 11, wherein the namespace is a machine virtualized in the host.

13. The method of claim 9 further comprising establishing a tunnel between the second-level managed forwarding element and an edge forwarding element.

14. The method of claim 13, wherein the edge forwarding element is a software switch that executes on another host machine along with a set of virtual machines.

15. For a network controller for managing managed forwarding elements that forward data in a network, a method for configuring first and second managed forwarding elements to perform logical L2 switching and L3 routing, the method comprising:

generating a first set of flow entries for configuring the first managed forwarding element to perform (i) a first logical L2 processing for a first logical L2 domain, (ii) a logical L3 processing, (iii) a network address translation (NAT) processing on packets to be sent to the second managed forwarding element, and (iv) a logical ingress L2 processing for a second logical L2 domain on the packets; and

generating a second set of flow entries for configuring the second managed forwarding element to perform a logical egress L2 processing for the second logical L2 domain on the packets.

16. The method of claim 15, wherein the NAT processing comprises (i) source NAT operations for translating a source address of a packet into another address and (ii) a destination NAT operations for translating a destination address of the packet into another address.

17. The method of claim 16, wherein the source and destination addresses are IP addresses.

18. The method of claim 16, wherein the first set of flow entries is further for configuring the first managed forwarding element to perform the destination NAT operations before performing the source NAT operations.

19. The method of claim 16, wherein the first set of flow entries is further for specifying that the first managed forwarding element to perform the destination NAT operations before performing the source NAT operations.

20. The method of claim 15 further comprising generating a tunnel between the first and second managed forwarding elements.