METHOD AND SYSTEM FOR IMPLEMENTING A MULTI-CHASSIS LINK AGGREGATION GROUP IN A NETWORK

• US 20120314715A1
• Filed: 06/07/2012
• Published: 12/13/2012
• Est. Priority Date: 06/08/2011
• Status: Active Grant

• Current Assignee: Dell Products LP (Dell Technologies Inc.)
• Original Assignee: Dell Products LP (Dell Technologies Inc.)
• Inventors: Janardhanan, Pathangi Narasimhan
• Granted Patent: US 9,692,686 B2
• Time in Patent Office: Days
• US Class Current: 370/402
• CPC Class Codes: H04L 45/245 Link aggregation, e.g. trunking
• CPC Class Codes: H04L 45/48 Routing tree calculation
• CPC Class Codes: H04L 45/586 of virtual routers
• 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

An information handling system is provided. The information handling system includes systems and methods for implementing a multi-chassis link aggregation group (MLAG) in a network. This may be achieved by connecting at least two switches to a plurality of servers, with at least one logical bridging device and at least one MLAG configured in between the network and the plurality of servers. The at least one logical bridging device may be associated with the at least one MLAG. The system may include at least one MLAG per logical bridging device, but may include more MLAGs than logical bridging devices.

Claims

1. An information handling system, comprising:

a first switch,

a second switch, the second switch being in communication with the first switch and the first and second switches being configured to communicate with a plurality of core physical bridging devices and with a set of servers; and

a logical bridging device, the first and second switches advertising connectivity to the logical bridging device.

2. The system of claim 1, wherein the first switch provides a first physical bridging device and the second switch provides a second physical bridging device, the logical bridging device being provided by the first and second physical bridging devices.

3. The system of claim 1, wherein the first and second switches comprise a plurality of ports and are configured to communicate with the set of servers through the plurality of ports.

4. The system of claim 3, wherein the plurality of ports comprises:

a first subset of ports, the first subset of ports configured to connect both the first and the second switches to at least one server among the set of servers; and

a second subset of ports configured to connect the first switch or the second switch, but not both, to the at least one server among the set of servers or to at least one other server among the set of servers.

5. The system of claim 4, wherein the first subset of ports supports a multi-chassis link aggregation group (MLAG).

6. The system of claim 2, wherein the first physical bridging device is configured to support at least two bridging device self-identifiers:

a first physical bridging device identifier and a logical bridging device identifier; and

the second physical bridging device is also configured to support at least two bridging device self-identifiers;

a second physical bridging device identifier and the logical bridging device identifier,

the first and second physical bridging devices using their respective self-identifiers when receiving packets from the plurality of physical bridging devices and from the set of servers.

7. The system of claim 2, wherein:

the first and second switches comprise top-of-rack switches;

each of the plurality of physical bridging devices comprises a routing bridge device; and

the logical bridging device comprises a logical routing bridge device.

8. An information handling system, the system comprising:

a plurality of bridging devices;

a first switch coupled to a second switch, the first and second switches being coupled to the plurality of physical bridging devices and advertising, to the plurality of physical bridging devices, a connection to a logical bridging device, the first and second switches each comprising a physical bridging device; and

a set of servers coupled to the first and second switches through a plurality of ports.

9. The system of claim 8, wherein the plurality of ports comprises:

a first subset of ports by which one or more or the set of servers are physically connected to both the first and second switches; and

a second subset of ports by which one or more of the set of servers are physically connected to the first switch or the second switch, but not both.

10. The system of claim 9, wherein the first subset of ports supports a multi-chassis link aggregation group (MLAG).

11. The system of claim 8, wherein the logical bridging device is provided by the first and second physical bridging devices, each of the first and second physical bridging devices being configured to support at least two bridging device identifiers.

12. The system of claim of claim 11, wherein:

the first physical bridging device is configured to support at least a first physical bridging device identifier and a logical bridging device identifier, the logical bridging device identifier being an identifier of the logical bridging device; and

the second physical bridging device is configured to support a second bridging device identifier and the logical bridging device identifier,

both the first and second physical bridging devices advertising, to the plurality of bridging devices, connectivity to the logical bridging device.

13. The system of claim 8, wherein the first and second physical bridging devices advertise connectivity to the logical bridging device to the plurality of bridging devices so that, in a logical topology of the system and relative to the plurality of physical bridging devices, the logical bridging device is located behind the first and second physical bridging devices and equidistant therefrom, and in front of the set of servers and connected to the subset of ports supporting the MLAG.

14. A method of implementing a multi-chassis link aggregation group (MLAG) in a network, the method comprising:

receiving a packet at one of a plurality of switches from one of a plurality of servers, each of the plurality of switches comprising a physical bridging device and advertising connectivity to a logical bridging device,

determining whether the packet was received at a port associated with the MLAG;

encapsulating the packet using an identifier of the logical bridging device in the header if the packet was received at a port associated with the MLAG;

encapsulating the packet using an identifier that is not the identifier of the logical bridging device if the packet was not received at a port associated with the MLAG; and

forwarding the encapsulated packet toward its destination through a plurality of bridging devices connected to the one of the plurality of servers through the plurality of switches.

15. The method of claim 14, further comprising:

determining whether the packet was received at a regular port; and

encapsulating the packet using an identifier of a physical bridging device provided by the receiving one of the plurality of switches.

16. The method of claim 15, wherein determining whether the packet was received at a port associated with the MLAG and determining whether the packet was received at a regular port further comprises using a lookup table to determine whether the packet was received at a regular port or an MLAG port.

17. The method of claim 16, wherein using the lookup table to determine whether the packet was received at a regular port or an MLAG port includes looking up a bridging device identifier associated with a source media access control (MAC) address of the packet.

18. The method of claim 17, wherein the lookup table includes a logical bridging device identifier and a physical bridging device identifier, the logical bridging device identifier being selected if the source MAC address indicates the packet was received at the MLAG port and the physical bridging device identifier being selected if the source MAC address indicates the packet was received at a regular port.

19. The method of claim 16, wherein using the lookup table to determine whether the packet was received at a regular port or an MLAG port includes looking up a bridging device identifier associated with an ingress port identifier of the packet.

20. The method of claim 19, wherein the lookup table includes a logical bridging device identifier and a physical bridging device identifier, the logical bridging device identifier being selected if the ingress port identifier indicates the packet was received at the MLAG port and the physical bridging device identifier being selected if the ingress port identifier indicates the packet was received at a regular port.