Virtual link aggregations across multiple fabric switches

• US 10,075,394 B2
• Filed: 07/21/2016
• Issued: 09/11/2018
• Est. Priority Date: 11/16/2012
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Brocade Communications Systems, LLC (Broadcom, Inc.)
• Inventors: Vobbilisetty, Suresh, Koganti, Phanidhar
• Primary Examiner(s): Crompton, Christopher R
• Application Number:
  US15/216,374
• Publication Number:
  US 20160330141A1
• Time in Patent Office: 782 Days
• Field of Search: 370217
• CPC Class Codes: H04L 12/4625 Single bridge functionality, e.g. connection of two networks over a single bridge
• CPC Class Codes: H04L 41/0654 using network fault recovery ring fault isolation or reconfiguration in loop networks without recovery actions by a network management system H04L12/437
• CPC Class Codes: H04L 45/245 Link aggregation, e.g. trunking
• CPC Class Codes: H04L 45/583 Stackable routers
• CPC Class Codes: H04L 45/66 Layer 2 routing, e.g. in Ethernet based MAN's
• CPC Class Codes: H04L 49/10 characterised by the switching fabric construction
• CPC Class Codes: H04L 49/111 Switch interfaces, e.g. port details
• CPC Class Codes: H04L 49/112 Switch control, e.g. arbitration
• CPC Class Codes: H04L 49/15 Interconnection of switching modules
• CPC Class Codes: H04L 49/25 Routing or path finding in a switch fabric
• CPC Class Codes: H04L 49/3009 Header conversion, routing tables or routing tags
• CPC Class Codes: H04L 49/70 Virtual switches
• CPC Class Codes: Y02D 30/50 in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

One embodiment of the present invention provides a switch. The switch is configurable to be a member of a first fabric switch. The switch includes a link aggregation module. During operation, the link aggregation module marks an ingress-switch field of a frame with a virtual switch identifier. This virtual switch identifier is associated with the switch and a second switch, which is a member of a second fabric switch, and is from a range of identifier associated with the first fabric switch and the second fabric switch. Each of the first fabric switch and the second fabric switch is operable to accommodate a plurality of switches and operate as a single switch.

Claims

1. A switch, comprising:

fabric circuitry configured to maintain a membership in a first network of interconnected switches, wherein the first network of interconnected switches is identified by a first fabric identifier; and

aggregation circuitry configured to;

identify a virtual link aggregation group comprising a second switch and a third switch in the first network of interconnected switches, wherein a second network of interconnected switches is reachable via the virtual link aggregation group, and wherein the second network of interconnected switches is identified by a second fabric identifier; and

maintain a mapping between the second and third switches and the virtual link aggregation group; and

forwarding circuitry configured to select, for a packet destined to the second network of interconnected switches, an egress switch between the second and third switches based on the mapping.

2. The switch of claim 1, wherein the virtual link aggregation group further comprises a first trunked link of the second switch and a second trunked link of the third switch.

3. The switch of claim 1, wherein the egress switch is selected based on an arbitration policy of the first network of interconnected switches, wherein the arbitration policy is based on one or more of:

load balancing, quality of service, security, network availability, and computing resources.

4. The switch of claim 2, wherein the arbitration policy is based on a hash function.

5. The switch of claim 1, wherein the forwarding circuitry is further configured to select a port via which the egress switch is reachable for the packet destined to the second network of interconnected switches.

6. The switch of claim 1, wherein the forwarding circuitry is configured to select the egress switch such that packets are distributed between the second and third switches.

7. The switch of claim 1, wherein the forwarding circuitry is further configured to obtain an inner frame by decapsulating an encapsulation header of an encapsulated packet.

8. A method, comprising:

maintaining, for a switch, a membership in a first network of interconnected switches, wherein the first network of interconnected switches is identified by a first fabric identifier;

identifying a virtual link aggregation group comprising a second switch and a third switch in the first network of interconnected switches, wherein a second network of interconnected switches is reachable via the virtual link aggregation group, and wherein the second network of interconnected switches is identified by a second fabric identifier;

maintaining a mapping between the second and third switches and the virtual link aggregation group; and

selecting, for a packet destined to the second network of interconnected switches, an egress switch between the second and third switches based on the mapping.

9. The method of claim 8, wherein the virtual link aggregation group further comprises a first trunked link of the second switch and a second trunked link of the third switch.

10. The method of claim 8, wherein the egress switch is selected based on an arbitration policy of the first network of interconnected switches, wherein the arbitration policy is based on one or more of:

load balancing, quality of service, security, network availability, and computing resources.

11. The method of claim 10, wherein the arbitration policy is based on a hash function.

12. The method of claim 8, further comprising selecting a port via which the egress switch is reachable for the packet destined to the second network of interconnected switches.

13. The method of claim 8, further comprising selecting the egress switch such that packets are distributed between the second and third switches.

14. The method of claim 8, further comprising obtaining an inner frame by decapsulating an encapsulation header of an encapsulated packet.

15. A computer system;

comprising;

a processor;

a storage device coupled to the processor and storing instructions that when executed by the processor cause the processor to perform a method, the method comprising;

maintaining a membership in a first network of interconnected switches, wherein the first network of interconnected switches is identified by a first fabric identifier;

identifying a virtual link aggregation group comprising a second computer system and a third computer system in the first network of interconnected switches, wherein a second network of interconnected switches is reachable via the virtual link aggregation group, and wherein the second network of interconnected switches is identified by a second fabric identifier;

maintaining a mapping between the second and third computer systems and the virtual link aggregation group; and

selecting, for a packet destined to the second network of interconnected switches, an egress system between the second and third computer systems based on the mapping.

16. The computer system of claim 15, wherein the virtual link aggregation group further comprises a first trunked link of the second computer system and a second trunked link of the third computer system.

17. The computer system of claim 15, wherein the egress system is selected based on an arbitration policy of the first network of interconnected switches, and wherein the arbitration policy is based on a hash function.

18. The computer system of claim 15, wherein the method further comprises selecting a port via which the egress system is reachable for the packet destined to the second network of interconnected switches.

19. The computer system of claim 15, wherein the method further comprises selecting the egress switch such that packets are distributed between the second and third computer systems.

20. The computer system of claim 18, wherein the method further comprises obtaining an inner frame by decapsulating an encapsulation header of an encapsulated packet.