System and method for dynamic link aggregation in a shared I/O subsystem

• US 7,404,012 B2
• Filed: 06/28/2002
• Issued: 07/22/2008
• Est. Priority Date: 05/06/2002
• Status: Expired due to Fees

• Current Assignee: Tahoe Research Limited (f/k/a Learndale Limited) (Vector Capital Corporation)
• Original Assignee: QLogic Corporation (Marvell Technology Group Limited)
• Inventors: Matters, Todd, Rimmer, Todd
• Primary Examiner(s): Flynn; Nathan
• Assistant Examiner(s): DENNISON, JERRY B
• Application Number:
  US10/186,188
• Publication Number:
  US 20030208631A1
• Time in Patent Office: 2,216 Days
• Field of Search: 709204-203, 709/250, 710/15, 710 20- 26
• US Class Current: 709/250
• CPC Class Codes: H04L 45/742 Route cache; Operation thereof
• CPC Class Codes: H04L 49/3009 Header conversion, routing tables or routing tags
• CPC Class Codes: H04L 49/358 Infiniband Switches
• CPC Class Codes: H04L 49/602 Multilayer or multiprotocol switching, e.g. IP switching
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]
• CPC Class Codes: H04L 67/63 Routing a service request depending on the request content or context
• CPC Class Codes: H04L 69/14 Multichannel or multilink protocols
• CPC Class Codes: H04L 69/18 Multiprotocol handlers, e.g. single devices capable of handling multiple protocols
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

A shared I/O subsystem for a plurality of computer systems. The shared I/O subsystem includes a plurality of physical I/O interfaces and a plurality of virtual I/O interfaces where each of the computer systems is communicatively coupled to one or more of the virtual I/O interfaces. The shared I/O subsystem also includes a forwarding function having a forwarding table that logically arranges the shared I/O subsystem into one or more logical LAN switches. Each of the logical LAN switches communicatively couples one or more of the virtual I/O interfaces to at least one of the physical I/O interfaces. For each of the logical LAN switches, the forwarding function receives a data packet from any one from the group of the physical I/O interfaces and the virtual I/O interfaces, and directs the data packet to at least one from the group of the physical I/O interfaces and the virtual I/O interfaces. Two or more of the physical I/O interfaces may be aggregated to form a logical I/O interface by selectively altering entries in the forwarding table without reconfiguring the computer systems.

Claims

1. A shared I/O subsystem for a plurality of computer systems comprising:

a plurality of physical I/O interfaces;

a plurality of virtual I/O interfaces, wherein each of the computer systems is communicatively coupled to one or more of the virtual I/O interfaces;

a forwarding function having a forwarding table that logically arranges the shared I/O subsystem into one or more logical LAN switches, wherein each of the logical LAN switches communicatively couples one or more of the virtual I/O interfaces to at least one of the physical I/O interfaces;

wherein, for each of the logical LAN switches, the forwarding function receives a data packet from any one from the group of the physical I/O interfaces and the virtual I/O interfaces, and directs the data packet to at least one from the group of the physical I/O interfaces and the virtual I/O interfaces; and

wherein two or more of the physical I/O interfaces are aggregated to form a single logical I/O interface by selectively altering entries in the forwarding table without reconfiguring the computer systems, and based on a destination address of a network packet, the forwarding function selects one or more of the physical I/O interfaces to deliver the network packet to a destination.

2. The shared I/O subsystem of claim 1, wherein two or more of the virtual I/O interfaces are aggregated by selectively altering the entries in the forwarding table.

3. The shared I/O subsystem of claim 1, wherein at least one of the physical I/O interfaces is operatively coupled to at least one of a network, an appliance, and a device.

4. The shared I/O subsystem of claim 3, wherein the network is a Storage Area Network.

5. The shared I/O subsystem of claim 3, wherein the network is an InterProcess Communications Network.

6. The shared I/O subsystem of claim 3, wherein the network is a Local Area Network.

7. The shared I/O subsystem of claim 3, wherein the network is a Wide Area Network.

8. The shared I/O subsystem of claim 3, wherein the network is a Metropolitan Area Network.

9. The shared I/O subsystem of claim 3, wherein the network is a System Area Network.

10. The shared I/O subsystem of claim 1, wherein one of the computer systems uses an operating system that is different from an operating system used by one other of the computer systems.

11. The shared I/O subsystem of claim 1, wherein the computer systems are communicatively coupled to one of the logical LAN switches.

12. The shared I/O subsystem of claim 11, wherein the computer systems are communicatively coupled to different ones of the logical LAN switches.

13. The shared I/O subsystem of claim 1, wherein the computer systems are interconnected to the shared I/O subsystem by a switching fabric.

14. The shared I/O subsystem of claim 13, wherein the switching fabric comprises a high speed, high bandwidth, and low latency fabric.

15. The shared I/O subsystem of claim 13, wherein the switching fabric includes a plurality of dedicated circuits, and wherein each of the computer systems communicates with any one of the computer systems via the dedicated circuits.

16. The shared I/O subsystem of claim 13, wherein the switching fabric uses an InfiniBand protocol.

17. The shared I/O subsystem of claim 1, wherein the data packet is filtered in the shared I/O subsystem.

18. The shared I/O subsystem of claim 1, wherein the shared I/O subsystem is located in one of the computer systems.

19. The shared I/O subsystem of claim 1, wherein at least one of the physical I/O interfaces is operatively coupled to a network unit including at least one of a switch, a hub, a router, and a bridge.

20. The shared VO subsystem of claim 1, wherein the forwarding function performs at least one of an address translation and an address filtering for the data packet.

21. In a shared I/O subsystem comprising

a plurality of physical I/O interfaces for a plurality of computer systems,

a plurality of virtual I/O interfaces, and

a forwarding function having a forwarding table, a method comprising:

communicatively coupling each of the computer systems to one or more of the virtual I/O interfaces;

logically arranging, with the forwarding table, the shared I/O subsystem into one or more logical LAN switches, wherein each of the logical LAN switches communicatively couples one or more of the virtual I/O interfaces to at least one of the physical I/O interfaces, and

wherein, for each of the logical LAN switches, the forwarding function receives a data packet from any one from the group of the physical I/O interfaces and the virtual I/O interfaces, and directs the data packet to at least one from the group of the physical I/O interfaces and the virtual I/O interfaces; and

aggregating two or more of the physical I/O interfaces to form a single logical I/O interface by selectively altering entries in the forwarding table without reconfiguring the computer systems and based on a destination address of a network packet, the following function selects one or more of the physical I/O interfaces to deliver the network packet to a destination.

22. A shared I/O subsystem comprising

a plurality of physical I/O interfaces for a plurality of computer systems,

a plurality of virtual I/O interfaces, and

a forwarding function having a forwarding table, comprising:

means for communicatively coupling each of the computer systems to one or more of the virtual I/O interfaces;

means for logically arranging, with the forwarding table, the shared I/O subsystem into one or more logical LAN switches, wherein each of the logical LAN switches communicatively couples one or more of the virtual I/O interfaces to at least one of the physical I/O interfaces, and wherein, for each of the logical LAN switches, the forwarding function receives a data packet from any one from the group of the physical I/O interfaces and the virtual I/O interfaces, and directs the data packet to at least one from the group of the physical I/O interfaces and the virtual I/O interfaces; and

means for aggregating two or more of the physical I/O interfaces to form a single logical I/O interface by selectively altering entries in the forwarding table without reconfiguring the computer systems and based on a destination address of a network packet, selecting one or more of the physical I/O interfaces to deliver the network packet to a destination.

25. The shared I/O subsystem of claim 22, wherein an Ethernet link and a Fibre Channel link are aggregated by the aggregate function and presented as a single link to the aggregate switching function.

23. A shared I/O subsystem for a plurality of computer systems, comprising:

at least one virtual I/O controller that is shared by a plurality of virtual network interface cards (NICs), the virtual NICs executed at each of the plurality of computer systems; and

each virtual NIC connects to a virtual port via a virtual bus;

an address cache maintained by the virtual I/O controller so that each virtual NIC maintains a unique network address;

an aggregate switching function that uses a forwarding table for moving of I/O packets between a plurality of virtual ports and to a plurality of network devices; and

an aggregate function that presents a plurality of physical links to the aggregate switching function as a single aggregated link to transfer network packets to the plurality of network devices;

wherein an outbound packet from one of the plurality of computer systems originates in a protocol stack executed above the virtual NIC and the virtual NIC transfers the outbound packet to a virtual port, and the virtual port delivers the packet to the aggregate switching function that uses the forwarding table to determine whether the outbound packet is to be delivered to another virtual port or to the aggregate function for delivery to one of the network devices; and

if the packet is destined for the aggregate function, then the aggregate function selects a link from the plurality of physical links to deliver the outbound packet to one or more of the network devices.

24. The shared I/O subsystem of claim 23, wherein an inbound network packet is received by the aggregate function and transfers the inbound packet to the aggregate switching function that determines a destination of the inbound packet using the forwarding table and based on the destination, the inbound packet is delivered to a virtual port that transfers the inbound packet to a destination virtual NIC.