Aggregated networking device failover system

An aggregated networking device failover system includes an aggregation connected device coupled to first and second aggregated networking devices. The aggregation connected device receives a first aggregation communication from the first aggregated networking device that identifies its first MAC address as an actor MAC address, and a second MAC address of the second aggregated networking device as an alternate actor MAC address. The aggregation connected device then associates the first and second MAC addresses with an aggregated link to the first and second aggregated networking devices. Subsequent to associating the first and second MAC addresses with the aggregated link, the aggregation connected device receives a second aggregation communication from the second aggregated networking device that identifies its second MAC address as an actor MAC address, and the aggregated link remains available in response to that second/actor MAC address being associated with the aggregated link.

BACKGROUND

The present disclosure relates generally to information handling systems, and more particularly to performing failover operations with aggregated networking information handling systems.

Information handling systems such as, for example, switch devices and other networking devices known in the art, are sometimes aggregated to provide an aggregated link to those switch devices. For example, the Virtual Link Trunking (VLT) protocol provided in VLT switch devices available from DELL® Inc. of Round Rock, Tex., United States, is a proprietary layer-2 (L2) link aggregation protocol that may provide server devices connected to the VLT switch devices a redundant, load-balancing connection (also called a VLT port channel) to a core network (e.g., via a Top Of Rack (TOR) switch device coupled to the VLT switch devices) in a loop-free environment without the need for the spanning tree protocol, and may also be utilized for uplinks/VLT port channels between the VLT switch devices and the core network (e.g., via the TOR switch device discussed above). Secondary VLT switch devices may be configured to provide for failover in the event of an unavailability of a primary VLT switch device, but such configurations are not mandatory for VLT functionality (e.g., as compared to peer-link port channel configurations, discovery interface configurations, and/or other mandatory VLT configurations known in the art).

For example, VLT switch devices may be optionally configured with an arbitrary VLT Media Access Control (MAC) address that can be used in failover or upgrade situations and, without that VLT MAC address, the VLT port channel provided by the VLT switch devices will “flap” (e.g., transition between “up” and “down”) when the primary VLT switch device becomes unavailable and a secondary VLT switch device attempts to perform primary VLT switch device re-election operations. In a specific example in which VLT MAC addresses are not used, a first VLT switch device operating as a primary VLT switch device and a second VLT switch device operating as a secondary VLT switch device are each connected to a TOR switch device. The first VLT switch device may provide a Link Aggregation Control Protocol (LACP) communication to the TOR switch device that provides its MAC address as an “actor” MAC address and the MAC address of the TOR switch device as a “partner” MAC address, and the TOR switch device may respond with an LACP communication to the first VLT switch device that provides its MAC address as an actor MAC address and the MAC address of the first VLT switch device as a partner MAC address. The second VLT switch device may then provide an LACP communication to the TOR switch device that provides the MAC address of the first VLT switch device as an actor MAC address and the MAC address of the TOR switch device as a partner MAC address, and the TOR switch device may respond with an LACP communication to the second VLT switch device that provides the MAC address of the TOR switch device as an actor MAC address and the MAC address of the first VLT switch device as a partner MAC address. As such, a VLT port channel will be established that is bound to the MAC address of the first VLT switch device and that includes ports on each of the first VLT switch device and the second VLT switch device.

In the event the first VLT switch device operating as the primary VLT switch device then becomes unavailable, its port will then be removed from the VLT port channel. The second VLT switch device will then attempt to become the primary VLT switch device by providing an LACP communication to the TOR switch device that provides its MAC address as an actor MAC address and the MAC address of the TOR switch device as a partner MAC address, and the TOR switch device may respond with an LACP communication to the second VLT switch device that provides the MAC address of the TOR switch device as an actor MAC address and the MAC address of the second VLT switch device as a partner MAC address. As will be appreciated by one of skill in the art in possession of the present disclosure, the changing of the LACP communication actor parameters (from the MAC address of the first VLT switch device to the MAC address of the second VLT switch device) will cause the TOR switch device to remove the port on the second VLT switch device from the VLT port channel such that the VLT port channel will no longer be associated with any ports (i.e., the VLT port channel will “flap”/transition from “up” to “down”) and cannot transmit data traffic, and will remain that way until a port on the second VLT switch device is added to a VLT port channel that is bound to the MAC address of the second VLT switch device.

In another specific example in which VLT MAC addresses are used to address the issues discussed above, a first VLT switch device operating as a primary VLT switch device and a second VLT switch device operating as a secondary VLT switch device are each connected to a TOR switch device. The first VLT switch device may provide an LACP communication to the TOR switch device that provides the VLT MAC address as an actor MAC address and the MAC address of the TOR switch device as a partner MAC address, and the TOR switch device may respond with an LACP communication to the first VLT switch device that provides its MAC address as an actor MAC address and the VLT MAC address as a partner MAC address. The second VLT switch device may then provide an LACP communication to the TOR switch device that provides the VLT MAC address as an actor MAC address and the MAC address of the TOR switch device as a partner MAC address, and the TOR switch device may respond with an LACP communication to the second VLT switch device that provides the MAC address of the TOR switch device as an actor MAC address and the VLT MAC address as a partner MAC address. As such, a VLT port channel will be established that is bound to the VLT MAC address and that includes ports on each of the first VLT switch device and the second VLT switch device.

Similarly as discussed above in the no-VLT MAC address scenario, in the event the first VLT switch device operating as the primary VLT switch device then becomes unavailable, its port will then be removed from the VLT port channel. However, the second VLT switch device will then attempt to become the primary VLT switch device by providing an LACP communication to the TOR switch device that provides the VLT MAC address as an actor MAC address and the MAC address of the TOR switch device as a partner MAC address, and the TOR switch device may respond with an LACP communication to the second VLT switch device that provides the MAC address of the TOR switch device as an actor MAC address and the VLT MAC address as a partner MAC address. As will be appreciated by one of skill in the art in possession of the present disclosure, the use of the VLT MAC address as discussed above eliminates the changing of the LACP communication actor parameters that occurs when a VLT MAC address is not utilized, and prevents the VLT port channel from “flapping” and the associated interruption in data transmission.

As such, when a primary VLT switch device performs a reboot operation that makes that primary VLT switch device unavailable, the VLT port channel will “flap” unless a network administrator or other user has performed the optional VLT MAC address configuration of the VLT switch devices discussed above. However, performing the optional configuration of the VLT MAC address for each of the VLT switch devices/nodes in an N-node VLT system can be complex and time-consuming. Furthermore, in the case of the manufacture/deployment of an Multi-domain/Extended VLT (E-VLT) topology, different VLT domains must be provided with different VLT MAC addresses, and conventional manufacturing/deployment processes are not able to configure the VLT switch devices with VLT MAC addresses automatically and deploy those VLT switch devices in a manner that ensures VLT switch devices configured with a common VLT MAC address will be utilized together.

Accordingly, it would be desirable to provide an aggregated switch device failover system that addresses the issues discussed above.

SUMMARY

According to one embodiment, an Information Handling System (IHS) includes a processing system; and a memory system that is coupled to the processing system and that includes instructions that, when executed by the processing system, cause the processing system to provide an aggregation connected engine that is configured to: receive, from a first aggregated networking device, a first aggregation communication that identifies: a first Media Access Control (MAC) address of the first aggregated networking device as an actor MAC address; and a second MAC address of a second aggregated networking device as an alternate actor MAC address, wherein the second aggregated networking device is aggregated with the first aggregated networking device and the second MAC address is different than the first MAC address; associate the first MAC address and the second MAC address with an aggregated link to the first aggregated networking device and the second aggregated networking device; and receive, from the second aggregated networking device subsequent to associating the first MAC address and the second MAC address with the aggregated link, a second aggregation communication that identifies the second MAC address as an actor MAC address, wherein the aggregated link remains available in response to the second MAC address that is identified as the actor MAC address being associated with the aggregated link.

DETAILED DESCRIPTION

Referring now toFIG.2, an embodiment of an aggregated networking device system200is illustrated. In the illustrated embodiment, the aggregated networking device system200includes a pair of aggregated switch devices202aand202b. In an embodiment, either or both of the aggregated switch devices202aand202bmay be provided by the IHS100discussed above with reference toFIG.1, and/or may include some or all of the components of the IHS100, and in specific examples may be provided by switch devices that are configured to operate according to the VLT protocol utilized in switch devices available from DELL® Inc., of Round Rock, Tex., United States. However, while illustrated and discussed as being provided by switch devices that are configured to operate according to a particular aggregation protocol, one of skill in the art in possession of the present disclosure will recognize that aggregated networking devices provided in the aggregated networking device system200may include any networking devices that may utilize any aggregation protocols that configure them to operate similarly as the aggregated switch devices202aand202bdiscussed below. As illustrated inFIG.2, the aggregated switch devices202aand202bmay be coupled together by an Inter-Chassis Link (ICL)204that may be provided by a plurality of aggregated links204a,204b, and up to204c.

The aggregated networking device system200also includes an aggregation connected device that is illustrated and described below as a Top Of Rack (TOR) switch device206. In an embodiment, the TOR switch devices206may be provided by the IHS100discussed above with reference toFIG.1, and/or may include some or all of the components of the IHS100, and in specific examples may be provided by a TOR switch device that may be included in a rack and that may couple the aggregated switch devices202aand202bto a core network (not illustrated). However, while illustrated and discussed as being provided by TOR switch device, one of skill in the art in possession of the present disclosure will recognize that TOR switch device in the aggregated networking device system200may be replaced with other aggregation connected devices (e.g., server devices coupled to the aggregated switch devices202aand202b) that may be configured to operate similarly as the TOR switch device206discussed below. As illustrated, the TOR switch device206may be coupled to the aggregated switch device202aby one or more links208a, and may be coupled to the aggregated switch device202bby one or more links208b, and the links208aand208bmay be aggregated to provide an aggregated link208(e.g., a VLT port channel in embodiments of the present disclosure that utilize the VLT protocol). However, while a specific aggregated networking device system200has been illustrated and described, one of skill in the art in possession of the present disclosure will recognize that the aggregated networking device failover system of the present disclosure may include a variety of components and component configurations while remaining within the scope of the present disclosure as well.

Referring now toFIG.3, an embodiment of an aggregated switch device300is illustrated that may provide either or both of the aggregated switch devices202aand202bdiscussed above with reference toFIG.2. As such, the aggregated switch device300may be provided by the IHS100discussed above with reference toFIG.1and/or may include some or all of the components of the IHS100, and in specific examples may be provided by a switch device that is configured to operate according to the VLT protocol utilized in switch devices available from DELL® Inc., of Round Rock, Tex., United States. However, while illustrated and discussed as a switch device configured to operate according to a particular protocol, one of skill in the art in possession of the present disclosure will recognize that the functionality of the aggregated switch device300discussed below may be provided by other devices that are configured to operate similarly as the aggregated switch device300discussed below. In the illustrated embodiment, the aggregated switch device300includes a chassis302that houses the components of the aggregated switch device300, only some of which are illustrated below. For example, the chassis302may house a processing system (not illustrated, but which may include the processor102discussed above with reference toFIG.1) and a memory system (not illustrated, but which may include the memory114discussed above with reference toFIG.1) that is coupled to the processing system and that includes instructions that, when executed by the processing system, cause the processing system to provide an aggregated switch engine304that is configured to perform the functionality of the aggregated switch engines and/or aggregated switch devices discussed below. One of skill in the art in possession of the present disclosure will appreciate that, in some embodiments, the functionality of the aggregated switch engine discussed below may be provided via modifications to a conventional LACP transmission (TX) state machine included in the aggregated switch device300, and may not require any modifications to a conventional LACP receiving (RX) state machine included in the aggregated switch device300.

The chassis302may also house a storage system (not illustrated, but which may include the storage108discussed above with reference toFIG.1) that is coupled to the aggregated switch engine304(e.g., via a coupling between the storage system and the processing system) and that includes an aggregated switch database306that is configured to store any of the information utilized by the aggregated switch engine304discussed below. The chassis302may also house a communication system308that is coupled to the aggregated switch engine304(e.g., via a coupling between the communication system308and the processing system) and that may be provided by a Network Interface Controller (NIC), wireless communication systems (e.g., BLUETOOTH®, Near Field Communication (NFC) components, WiFi components, etc.), and/or any other communication components that would be apparent to one of skill in the art in possession of the present disclosure. However, while a specific aggregated switch device300has been illustrated and described, one of skill in the art in possession of the present disclosure will recognize that aggregated switch devices (or other devices operating according to the teachings of the present disclosure in a manner similar to that described below for the aggregated switch device300) may include a variety of components and/or component configurations for providing conventional switch device functionality, as well as the functionality discussed below, while remaining within the scope of the present disclosure as well.

Referring now toFIG.4, an embodiment of a Top Of Rack (TOR) switch device400is illustrated that may provide the TOR switch device206discussed above with reference toFIG.2. As such, the TOR switch device400may be provided by the IHS100discussed above with reference toFIG.1and/or may include some or all of the components of the IHS100. Furthermore, while illustrated and discussed as being provided by a TOR switch device, one of skill in the art in possession of the present disclosure will recognize that the functionality of the TOR switch device400discussed below may be provided by other aggregation connected devices (e.g., server devices) that are configured to operate similarly as the TOR switch device400discussed below. In the illustrated embodiment, the TOR switch device400includes a chassis402that houses the components of the TOR switch device400, only some of which are illustrated below. For example, the chassis402may house a processing system (not illustrated, but which may include the processor102discussed above with reference toFIG.1) and a memory system (not illustrated, but which may include the memory114discussed above with reference toFIG.1) that is coupled to the processing system and that includes instructions that, when executed by the processing system, cause the processing system to provide a TOR switch engine404that is configured to perform the functionality of the aggregation connected engines, TOR switch engines, and/or TOR switch devices discussed below. One of skill in the art in possession of the present disclosure will appreciate that, in some embodiments, the functionality of the TOR switch engine discussed below may be provided via modifications to a conventional LACP receiving (RX) state machine included in the TOR switch device400, and may not require any modifications to a conventional LACP transmission (TX) state machine included in the TOR switch device400.

The chassis402may also house a storage system (not illustrated, but which may include the storage108discussed above with reference toFIG.1) that is coupled to the TOR switch engine404(e.g., via a coupling between the storage system and the processing system) and that includes a TOR switch database406that is configured to store any of the information utilized by the TOR switch engine404discussed below. The chassis402may also house a communication system408that is coupled to the TOR switch engine404(e.g., via a coupling between the communication system408and the processing system) and that may be provided by a Network Interface Controller (NIC), wireless communication systems (e.g., BLUETOOTH®, Near Field Communication (NFC) components, WiFi components, etc.), and/or any other communication components that would be apparent to one of skill in the art in possession of the present disclosure. However, while a specific TOR switch device400has been illustrated, one of skill in the art in possession of the present disclosure will recognize that TOR switch devices (or other devices operating according to the teachings of the present disclosure in a manner similar to that described below for the TOR switch device400) may include a variety of components and/or component configurations for providing conventional switch device functionality, as well as the functionality discussed below, while remaining within the scope of the present disclosure as well.

Referring now toFIG.5, an embodiment of a method500for performing failover operations with aggregated networking devices is illustrated. As discussed below, the systems and methods of the present disclosure provide for the identification of an actor and alternate actor for an aggregated link by aggregated networking devices associated with that aggregated link, which allows that aggregated link to remain available when a primary aggregated networking device identified as the actor becomes unavailable and the secondary aggregated networking device identified as the alternate actor performs failover operations and becomes a primary aggregated networking device. For example, the aggregated networking device failover system of the present disclosure includes an aggregation connected device coupled to first and second aggregated networking devices. The aggregation connected device receives a first aggregation communication from the first aggregated networking device that identifies a first MAC address of the first aggregated networking device as an actor MAC address, and a second MAC address of the second aggregated networking device as an alternate actor MAC address. The aggregation connected device then associates the first and second MAC addresses with an aggregated link to the first and second aggregated networking devices. Subsequent to associating the first and second MAC addresses with the aggregated link, the aggregation connected device receives a second aggregation communication from the second aggregated networking device that identifies the second MAC address of the second aggregated networking device as an actor MAC address, and the aggregated link remains available in response to that second MAC address/actor MAC address being associated with the aggregated link. As such, aggregated link “flapping” is eliminated in aggregated networking device failover scenarios without the need to configure each aggregated networking device with a common aggregation MAC address.

With reference toFIG.6, an embodiment of an aggregation communication600is illustrated that may be utilized during the method500as discussed below. One of skill in the art in possession of the present disclosure will recognize that the aggregation communication600illustrated inFIG.6is a modified Link Aggregation Control Protocol (LACP) aggregation communication, but may be provided by another aggregation communications while remaining within the scope of the present disclosure as well. As illustrated inFIG.6, the aggregation communication600may include a preamble602, a destination Media Access Control (MAC) address604, a source MAC address606, an ether type608, a sub type610, an LACP version612, a Type-Length-Value (TLV) data structure614, and a Frame Check Sequence (FCS)616. Furthermore,FIG.6illustrates how the TLV data structure614includes TLV actor information614athat includes a type section that identifies actor information (e.g., 0x01), a length section (e.g., 0x14), and a value section that identifies an actor system priority, an actor MAC address, an actor key, an actor port priority, an actor port, and an actor state, and includes a reserved section. The TLV data structure614also includes TLV partner information614bthat includes a type section that identifies partner information (e.g., 0x02), a length section (e.g., 0x14), and a value section that identifies a partner system priority, a partner MAC address, a partner key, a partner port priority, a partner port, and a partner state, and includes a reserved section.

The TLV data structure614also includes TLV collector information614cthat includes a type section that identifies collector information (e.g., 0x03), a length section (e.g., 0x10), and a value section that identifies a collector maximum delay and includes a reserved section. The TLV data structure614also includes TLV terminator information614dthat includes a type section that identifies terminator information (e.g., 0x00), a length section (e.g., 0x00), and a value section that includes padding (e.g., typically around 50 bytes of space). The TLV data structure614also includes TLV alternate actor information614ethat identifies alternate actor information (e.g., 0x04), a length section (e.g., 0x06), and a value section that identifies an alternate actor MAC address and that may include padding, and one of skill in the art in possession of the present disclosure will appreciate that the TLV alternate actor information614ein the TLV data structure614provides a modification to conventional TLV data structures in conventional LACP aggregation communications. In an embodiment, the aggregated networking device failover system of the present disclosure may utilize the padding in the value section of the TLV terminator information614dto provide the TLV alternate actor information614e(e.g., with approximately 44 bytes in the padding in the TLV alternate actor information614ebeing the portion of the padding from the TLV terminator information614dthat is not used for the TLV alternate actor information614e). However, while a particular aggregation communication is illustrated and described herein, one of skill in the art in possession of the present disclosure will appreciate how the aggregated networking device failover functionality may be accomplished using other communications and/or communication data structures while remaining within the scope of the present disclosure as well.

The method500begins at block502where an aggregation connected device receives an aggregation communication from an aggregated networking device. In an embodiment, at block502, the aggregated networking devices202aand202bmay generate and transmit aggregation communications to the TOR switch device206. For example, with reference toFIG.7A, the aggregated switch engine304in the aggregated networking device202a/300may generate an aggregation communication and may perform aggregation communication transmission operations700that include transmitting the aggregation communication via its communication system308and through the link(s)208asuch that the aggregation communication is received by the TOR switch engine404in the TOR switch device206/400via its communication system408.

In embodiments in which the aggregation communication600discussed above with reference toFIG.6is utilized, the aggregation communication received by the TOR switch device206/400from the aggregated networking device202a/300at block502may identify a MAC address of the aggregated networking device202aas the actor MAC address in the value section of the TLV actor information614a, a MAC address of the TOR switch device206/400as the partner MAC address in the value section of the TLV partner information614b, and a MAC address of the aggregated networking device202b/300as the alternate actor MAC address in the value section of the TLV alternate actor information614e. Furthermore, while not discussed above, the aggregation communication received by the TOR switch device206/400from the aggregated networking device202a/300at block502may include any of the other information discussed above with reference toFIG.6as well.

In another example, with reference toFIG.8A, the aggregated switch engine304in the aggregated networking device202b/300may generate an aggregation communication and may perform aggregation communication transmission operations800that include transmitting the aggregation communication via its communication system308and through the link(s)208bsuch that the aggregation communication is received by the TOR switch engine404in the TOR switch device206/400via its communication system408. In embodiments in which the aggregation communication600discussed above with reference toFIG.6is utilized, the aggregation communication received by the TOR switch device206/400from the aggregated networking device202b/300at block502may identify a MAC address of the aggregated networking device202bas the actor MAC address in the value section of the TLV actor information614a, a MAC address of the TOR switch device206/400as the partner MAC address in the value section of the TLV partner information614b, and a MAC address of the aggregated networking device202a/300as the alternate actor MAC address in the value section of the TLV alternate actor information614e. Furthermore, while not discussed above, the aggregation communication received by the TOR switch device206/400from the aggregated networking device202b/300at block502may include any of the other information discussed above with reference toFIG.6as well.

As will be appreciated by one of skill in the art in possession of the present disclosure, while the examples below describe the identification of alternate actors in aggregation communications, the TOR switch device206/400of the present disclosure may be configured to receive aggregation communications that do not identify an alternate actor, and may operate to handle those aggregation communications in a conventional manner and similarly as described above.

The method500then proceeds to decision block504where it is determined whether an aggregated link is associated with an actor or alternate actor. In an embodiment, at decision block504and in response to receiving the aggregation communication, the TOR switch engine404in the TOR switch device206/400may determine whether an aggregated link coupling the TOR switch device206/400to the aggregated networking devices202aand202bis associated with an actor MAC address or an alternate actor MAC address in its TOR switch database406. As discussed below, the aggregated networking devices202aand202bmay have each previously identified their own MAC address as an actor MAC address and the MAC address of the other aggregated networking device as an alternate actor MAC address to the TOR switch device206in order to have that actor MAC address and alternate actor MAC address associated with a aggregated link to the TOR switch device206(e.g., in the TOR switch database406), and thus the TOR switch engine404in the TOR switch device206/400may check the TOR switch database406for the association of an actor MAC address and alternate actor MAC address with that aggregated link upon receiving an aggregation communication.

If, at decision block504, it is determined that an aggregated link is not associated with an actor or alternate actor, the method500proceeds to block506where the aggregation connected device associates the aggregated networking devices with an aggregated link. Continuing with the example in which the aggregation communication was received from the aggregated networking device202aand in embodiments in which the aggregation communication600discussed above with reference toFIG.6is utilized, at block506and in response to determining that an aggregated link is not associated with an actor or alternate actor in its TOR switch database406at decision block504, the TOR switch engine404in the TOR switch device206/400may associate the aggregated networking devices202aand202bwith the aggregated link208that will be provided by the links208aand208bby associating that aggregated link208with the actor MAC address provided in the value section of the TLV actor information614aincluded in the aggregation communication received from the aggregated networking device202a(i.e., the MAC address of the aggregated networking device202ain this example) in its TOR switch database406, and by associating the aggregated link208with the alternate actor MAC address provided in the value section of the TLV alternate actor information614eincluded in the aggregation communication received from the aggregated networking device202a(i.e., the MAC address of the aggregated networking device202bin this example) in its TOR switch database406.

Furthermore, with reference toFIG.7B, the TOR switch engine404in the TOR switch device206/400may generate an aggregation communication and may perform aggregation communication transmission operations702that include transmitting the aggregation communication via its communication system408and to the aggregated switch device202a. In embodiments in which the aggregation communication600discussed above with reference toFIG.6is utilized, the aggregation communication transmitted by the TOR switch device206/400to the aggregated networking device202a/300at block506may identify a MAC address of the TOR switch device206/400as the actor MAC address in the value section of the TLV actor information614a, and a MAC address of the aggregated networking device202aas the partner MAC address in the value section of the TLV partner information614b. Furthermore, while not discussed above, the aggregation communication transmitted by the TOR switch device206/400to the aggregated networking device202a/300at block506may include any of the other information discussed above with reference toFIG.6as well. Following the association of the aggregated link208with the link208ato the aggregated networking device202ain response to the aggregation communication transmission operation700, as well as the association of the aggregated link208with link208bto the aggregated networking device202bin response to the aggregation communication transmission operation800, the links208aand208bare aggregated to provide the aggregated link208, and that aggregated link208may be utilized to transmit data between the aggregated networking devices202a/202band the TOR switch device206. The method500may then return to block502.

Continuing with the example in which the aggregation communication was received from the aggregated networking device202band in embodiments in which the aggregation communication600discussed above with reference toFIG.6is utilized, at block506and in response to determining that an aggregated link is not associated with an actor or alternate actor in its TOR switch database406at decision block504, the TOR switch engine404in the TOR switch device206/400may associate the aggregated networking devices202aand202bwith the aggregated link208that will be provided by the links208aand208bby associating the aggregated link208with the actor MAC address provided in the value section of the TLV actor information614aincluded in the aggregation communication received from the aggregated networking device202b(i.e., the MAC address of the aggregated networking device202bin this example) in its TOR switch database406, and by associating the aggregated link208with the alternate actor MAC address provided in the value section of the TLV alternate actor information614eincluded in the aggregation communication received from the aggregated networking device202b(i.e., the MAC address of the aggregated networking device202ain this example) in its TOR switch database406.

Furthermore, with reference toFIG.8B, the TOR switch engine404in the TOR switch device206/400may generate an aggregation communication and may perform aggregation communication transmission operations802that include transmitting the aggregation communication via its communication system408and to the aggregated switch device202a. In embodiments in which the aggregation communication600discussed above with reference toFIG.6is utilized, the aggregation communication transmitted by the TOR switch device206/400to the aggregated networking device202b/300at block506may identify a MAC address of the TOR switch device206/400as the actor MAC address in the value section of the TLV actor information614a, and a MAC address of the aggregated networking device202bas the partner MAC address in the value section of the TLV partner information614b. Furthermore, while not discussed above, the aggregation communication transmitted by the TOR switch device206/400to the aggregated networking device202b/300at block506may include any of the other information discussed above with reference toFIG.6as well. Following the association of the aggregated link208with the link208bto the aggregated networking device202bin response to the aggregation communication transmission operation800, as well as the association of the aggregated link208with link208ato the aggregated networking device202ain response to the aggregation communication transmission operation700, the links208aand208bare aggregated to provide the aggregated link208, and that aggregated link208may be utilized to transmit data between the aggregated networking devices202a/202band the TOR switch device206. The method500may then return to block502.

If, at decision block504, it is determined that an aggregated link is associated with an actor or alternate actor, the method500proceeds to decision block508where it is determined whether the actor or alternate actor associated with the aggregated link correspond to the actor or alternate actor identified in the aggregation communication from the aggregated networking device. In an embodiment, at decision block508and in response to determine that the aggregated link208coupling the TOR switch device206/400to the aggregated networking devices202aand202bis associated with an actor or alternate actor in its TOR switch database406, the TOR switch engine404in the TOR switch device206/400may determine whether the actor or alternate actor identified in the aggregation communication received at block502corresponds to the actor or alternate actor associated with the aggregated link208.

Continuing with the example in which the aggregation communication was received from the aggregated networking device202aand in embodiments in which the aggregation communication600discussed above with reference toFIG.6is utilized, at decision block508and in response to determining that the aggregated link208is associated with an actor or alternate actor in its TOR switch database406at decision block504, the TOR switch engine404in the TOR switch device206/400may determine whether the actor MAC address provided in the value section of the TLV actor information614aincluded in the aggregation communication received from the aggregated networking device202a(i.e., the MAC address of the aggregated networking device202ain this example) matches the actor MAC address or alternate actor MAC address associated with the aggregated link208in its TOR switch database406

Continuing with the example in which the aggregation communication was received from the aggregated networking device202band in embodiments in which the aggregation communication600discussed above with reference toFIG.6is utilized, at decision block508and in response to determining that the aggregated link208is associated with an actor or alternate actor in its TOR switch database406at decision block504, the TOR switch engine404in the TOR switch device206/400may determine whether the actor MAC address provided in the value section of the TLV actor information614aincluded in the aggregation communication received from the aggregated networking device202b(i.e., the MAC address of the aggregated networking device202bin this example) matches the actor MAC address or alternate actor MAC address associated with the aggregated link208in its TOR switch database406.

If, at decision block508, it is determined that the actor or alternate actor associated with the aggregated link correspond to the actor or alternate actor identified in the aggregation communication from the aggregated networking device, the method500proceeds to block510where the aggregation connected device maintains the aggregated link with the aggregated networking device. Continuing with the example in which the aggregation communication was received from the aggregated networking device202aand in embodiments in which the aggregation communication600discussed above with reference toFIG.6is utilized, at block510and in response to determining that the actor or alternate actor associated with the aggregated link208correspond to the actor or alternate actor identified in the aggregation communication from the aggregated networking device202aat decision block508, the TOR switch engine404in the TOR switch device206/400may maintain the aggregate link208with the aggregated networking device202a.

Furthermore, with reference back toFIG.7B, the TOR switch engine404in the TOR switch device206/400may then generate an aggregation communication and may perform the aggregation communication transmission operations702similarly as discussed above that include transmitting the aggregation communication via its communication system408and to the aggregated switch device202a. In embodiments in which the aggregation communication600discussed above with reference toFIG.6is utilized, the aggregation communication transmitted by the TOR switch device206/400to the aggregated networking device202a/300at block510may identify a MAC address of the TOR switch device206/400as the actor MAC address in the value section of the TLV actor information614a, and a MAC address of the aggregated networking device202aas the partner MAC address in the value section of the TLV partner information614b. Furthermore, while not discussed above, the aggregation communication transmitted by the TOR switch device206/400to the aggregated networking device202a/300at block510may include any of the other information discussed above with reference toFIG.6as well. As such, at block510, the aggregated link208may be utilized to transmit data between the aggregated networking device202aand the TOR switch device206.

Continuing with the example in which the aggregation communication was received from the aggregated networking device202band in embodiments in which the aggregation communication600discussed above with reference toFIG.6is utilized, at block510and in response to determining that the actor or alternate actor associated with the aggregated link208correspond to the actor or alternate actor identified in the aggregation communication from the aggregated networking device202bat decision block508, the TOR switch engine404in the TOR switch device206/400may maintain the aggregate link208with the aggregated networking device202b.

Furthermore, with reference back toFIG.8B, the TOR switch engine404in the TOR switch device206/400may then generate an aggregation communication and may perform aggregation communication transmission operations802that include transmitting the aggregation communication via its communication system408and to the aggregated switch device202b. In embodiments in which the aggregation communication600discussed above with reference toFIG.6is utilized, the aggregation communication transmitted by the TOR switch device206/400to the aggregated networking device202b/300at block510may identify a MAC address of the TOR switch device206/400as the actor MAC address in the value section of the TLV actor information614a, and a MAC address of the aggregated networking device202bas the partner MAC address in the value section of the TLV partner information614b. Furthermore, while not discussed above, the aggregation communication transmitted by the TOR switch device206/400to the aggregated networking device202b/300at block510may include any of the other information discussed above with reference toFIG.6as well. As such, at block510, the aggregated link208may be utilized to transmit data between the aggregated networking device202band the TOR switch device206.

If, at decision block508, it is determined that the actor or alternate actor associated with the aggregated link does not correspond to the actor or alternate actor identified in the aggregation communication from the aggregated networking device, the method500proceeds to block512where the aggregation connected device ignores the aggregation communication from the aggregated networking device. In an embodiment, at block512and in response to determining that the actor or alternate actor associated with the aggregated link208do not correspond to the actor or alternate actor identified in the aggregation communication from the aggregated networking device202aor202bat decision block508, the TOR switch engine404in the TOR switch device206/400with ignore the aggregation communication received from the aggregated networking device202aor202bat block502(e.g., that link will not be included in the aggregated link208, preventing data packets from being transmitted via that link, while allowing control packets (e.g., LLDP control packets, LACP control packets, etc.).

With reference toFIG.9, an example of the performance of the method500is provided below to illustrate how the aggregated networking device failover system of the present disclosure addresses the issues with conventional aggregated networking device failover systems discussed above. In this example, the aggregated switch device202ais initially configured as a primary aggregated switch device and the aggregated switch device202bis initially configured as a secondary aggregated switch device. At block502, the aggregated switch device202amay provide an aggregation communication to the TOR switch device206that provides the MAC address of the aggregated switch device202aas an actor MAC address, the MAC address of the aggregated switch device202bas an alternate actor MAC address, and the MAC address of the TOR switch device206as a partner MAC address. At decision block504, the TOR switch device206may determine that an aggregated link is not associated with an actor or alternate actor, and may proceed to block506to associate the actor MAC address (e.g., the MAC address of the aggregated switch device202ain this example) and the alternate actor MAC address (e.g., the MAC address of the aggregated switch device202bin this example) with the aggregated link208. The TOR switch device206may then respond with an aggregation communication to the aggregated switch device202athat provides MAC address of the TOR switch device206as an actor MAC address, and the MAC address of the aggregated switch device202aas a partner MAC address.

In the event the aggregated switch device202aoperating as the primary VLT switch device then becomes unavailable (as illustrated by element900inFIG.9), its port(s) will be removed from the aggregated link208. The aggregated switch device202bwill then attempt to become the primary aggregated switch device by providing an aggregation communication to the TOR switch device206at block502that provides the MAC address of the aggregated switch device202bas an actor MAC address and the MAC address of the TOR switch device206as a partner MAC address. At decision block504, the TOR switch device206may determine that the aggregated link208is associated with an actor and alternate actor, and the method500may proceed to decision block508where the TOR switch device206will match the actor MAC address provided by the aggregated switch device202b(i.e., the MAC address of the aggregated switch device202b) with the alternate actor MAC address previously provided by the aggregated switch device202aand associated with the aggregated link208(i.e., the MAC address of the aggregated switch device202b), and thus the TOR switch device206will maintain the aggregated link208with the aggregated networking device202bat block510, and may respond with an aggregation communication to the aggregated switch device202bthat provides the MAC address of the TOR switch device as an actor MAC address and the MAC address of the aggregated switch device202bas a partner MAC address. Furthermore, in some embodiments, the TOR switch device206may then replace the actor MAC address previously provided by the aggregated switch device202awith the actor MAC address provided by the aggregated switch device202b. As such, the association of the aggregated link208with an actor MAC address and alternate actor MAC address prevents the aggregated link208from “flapping” (and the associated interruption in data transmission) during failover operations without the need to configure each of the aggregated switch devices202aand202bwith a common MAC address like the VLT MAC address discussed above.

As illustrated inFIG.10, in an embodiment, the aggregated switch device202athat became unavailable may be replaced with an aggregated switch device1000. In response, at decision block502the aggregated switch device202bmay provide an aggregation communication to the TOR switch device206that provides the MAC address of the aggregated switch device202bas an actor MAC address, the MAC address of the aggregated switch device1000as an alternate actor MAC address, and the MAC address of the TOR switch device206as a partner MAC address. At decision block504, the TOR switch device206may determine that the aggregated link208is not associated with the alternate actor identified by the aggregated switch device202b, and may proceed to block506to associate the alternate actor MAC address (e.g., the MAC address of the aggregated switch device1000) with the aggregated link208. The TOR switch device206may then respond with an aggregation communication to the aggregated switch device202bthat provides the MAC address of the TOR switch device206as an actor MAC address, and the MAC address of the aggregated switch device202bas a partner MAC address. As will be appreciated by one of skill in the art in possession of the present disclosure, in the event the aggregated switch device202bbecomes unavailable (e.g., similarly to the aggregated switch device202abecoming unavailable as discussed above with reference toFIG.9), the aggregated link208will be maintained with the aggregated switch device1000via the same techniques discussed above by which it was maintained with the aggregated switch device202b.

Thus, systems and methods have been described that provide for the identification of an actor and alternate actor by VLT nodes associated with an VLT port channel, which allows that VLT port channel to remain available when a primary VLT node identified as the actor becomes unavailable and the secondary VLT node identified as the alternate actor performs failover operations and becomes a primary VLT node. For example, the VLT failover system of the present disclosure includes an aggregation connected device coupled to first and second VLT nodes. The aggregation connected device receives a first aggregation communication from the first VLT node that identifies its first MAC address of the first VLT node as an actor MAC address, and a second MAC address of the second VLT node as an alternate actor MAC address. The aggregation connected device then associates the first and second MAC addresses with a VLT port channel provided with the first and second VLT nodes. Subsequent to associating the first and second MAC addresses with the VLT port channel, the aggregation connected device receives a second aggregation communication from the second VLT node that identifies the second MAC address as an actor MAC address, and the VLT port channel remains available in response to that second MAC address/actor MAC address having been previously associated with the VLT port channel as an alternate actor MAC address. As such, VLT port channel “flapping” is eliminated in VLT node failover scenarios without the need to configure each aggregated VLT node with a common VLT MAC address.