Abstract: Techniques are described to provide layer 2 (L2) circuit failover in the event connectivity to an Ethernet Virtual Private Network (EVPN) instance is lost. For example, if one of multi-homed provider edge (PE) devices loses connectivity to the EVPN instance, the PE device may mark its customer-facing interface as down and propagate the interface status to the access node such that the access node may update its routing information to switch L2 circuits to another one of the multi-homed PE devices having reachability to the EVPN instance. In some examples, the plurality of PE devices may further implement Connectivity Fault Management (CFM) techniques to propagate the interface status to the access node such that the access node may update its forwarding information to send traffic on a different L2 circuit to another one of the multi-homed PE devices having reachability to the EVPN instance.

Abstract: Techniques are described to provide layer 2 (L2) circuit failover in the event connectivity to an Ethernet Virtual Private Network (EVPN) instance is lost. For example, if one of multi-homed provider edge (PE) devices loses connectivity to the EVPN instance, the PE device may mark its customer-facing interface as down and propagate the interface status to the access node such that the access node may update its routing information to switch L2 circuits to another one of the multi-homed PE devices having reachability to the EVPN instance. In some examples, the plurality of PE devices may further implement Connectivity Fault Management (CFM) techniques to propagate the interface status to the access node such that the access node may update its forwarding information to send traffic on a different L2 circuit to another one of the multi-homed PE devices having reachability to the EVPN instance.

Abstract: Techniques are described to provide layer 2 (L2) circuit failover in the event connectivity to an Ethernet Virtual Private Network (EVPN) instance is lost. For example, if one of multi-homed provider edge (PE) devices loses connectivity to the EVPN instance, the PE device may mark its customer-facing interface as down and propagate the interface status to the access node such that the access node may update its routing information to switch L2 circuits to another one of the multi-homed PE devices having reachability to the EVPN instance. In some examples, the plurality of PE devices may further implement Connectivity Fault Management (CFM) techniques to propagate the interface status to the access node such that the access node may update its forwarding information to send traffic on a different L2 circuit to another one of the multi-homed PE devices having reachability to the EVPN instance.

Abstract: Techniques are disclosed for an Ethernet Virtual Private Network (EVPN) Virtual Private Wire Service (VPWS) network with service interface-aware forwarding. In one example, a first network device signals to a second network device, using EVPN route advertisements, a multi-service service tunnel to transport network packets for a plurality of services. The services are identifiable by virtual local area network (VLAN) identifiers in the packets. The first network device is configured with a single transport interface for the service tunnel and the single transport interface is configured with respective service interfaces for the services. The first network device detects failure of a failed service interface of the service interfaces and outputs, in response to the failure, an EVPN route withdrawal message for the service tunnel that identifies the service corresponding to the failed service interface.

Abstract: The techniques describe detecting connectivity failure of an aggregated interface. To monitor connectivity of the aggregated interface, a packet processor of a plurality of packet processors is set as a session master responsible for managing an active forwarding plane connectivity detection session with a peer session master node. The other local packet processors of the virtual network node are selected as session standby nodes that each have a passive forwarding plane connectivity detection session running to the peer session master node. If a session master node goes down (i.e., by link or node failure), one of the local session standby nodes may detect the failure and is set as a new session master node by activating its passive session having the same session parameters.

Abstract: The techniques describe forwarding multicast traffic using a multi-level cache in a network device forwarding plane for determining a set of outgoing interfaces of the network device on which to forward the multicast traffic. For example, a multi-level cache is configured to store a multicast identifier of a multicast packet and multicast forwarding information associated with the multicast identifier, such as identification of one or more egress packet processors of the network device to which the multicast packet is to be sent for forwarding to the set of one or more egress network devices, and/or outgoing interfaces of the network device toward each egress network device of the set of one or more egress network devices. The multi-level cache is also configured to store respective multicast identifiers that are to be encapsulated with outgoing multicast packets that are forwarded to the set of one or more egress network devices.

Abstract: A method includes receiving, by processing circuitry of a first network device, an indication of a logical address associated with an interface to a second network device and adding, by the processing circuitry, an entry to a forwarding table of the first network device, the entry in the forwarding table specifying the logical address. The method further includes adding, by the processing circuitry, an entry to a resolver database of the first network device to which the entry in the forwarding table specifying the logical address points and resolving, by the processing circuitry, the logical address to a hardware address of the second network device.

Abstract: Techniques are disclosed for an Ethernet Virtual Private Network (EVPN) Virtual Private Wire Service (VPWS) network with service interface-aware forwarding. In one example, a first network device signals to a second network device, using EVPN route advertisements, a multi-service service tunnel to transport network packets for a plurality of services. The services are identifiable by virtual local area network (VLAN) identifiers in the packets. The first network device is configured with a single transport interface for the service tunnel and the single transport interface is configured with respective service interfaces for the services. The first network device detects failure of a failed service interface of the service interfaces and outputs, in response to the failure, an EVPN route withdrawal message for the service tunnel that identifies the service corresponding to the failed service interface.

Abstract: A device may determine a link aggregation group (LAG) that aggregates links that includes a first group of links that connects the device to a first provider edge (PE) device and a second group of links that connects the device to the second PE device, where the first PE device and the second PE device are on an Ethernet virtual private network (EVPN) and are multi-homed PE devices for the device, and where the first PE device provides a local connection to a customer edge (CE) device for the device. The device may receive a message from the first PE device indicating that the first PE device lacks a connection with the EVPN, and may send, based on the message, traffic intended for the CE device via the first PE device and traffic intended for the EVPN via the second PE device and not the first PE device.

Abstract: Techniques are described to provide layer 2 (L2) circuit failover in the event connectivity to an Ethernet Virtual Private Network (EVPN) instance is lost. For example, if one of multi-homed provider edge (PE) devices loses connectivity to the EVPN instance, the PE device may mark its customer-facing interface as down and propagate the interface status to the access node such that the access node may update its routing information to switch L2 circuits to another one of the multi-homed PE devices having reachability to the EVPN instance. In some examples, the plurality of PE devices may further implement Connectivity Fault Management (CFM) techniques to propagate the interface status to the access node such that the access node may update its forwarding information to send traffic on a different L2 circuit to another one of the multi-homed PE devices having reachability to the EVPN instance.

Abstract: Techniques are disclosed for an Ethernet Virtual Private Network (EVPN) Virtual Private Wire Service (VPWS) network with service interface-aware forwarding. In one example, a first network device signals to a second network device, using EVPN route advertisements, a multi-service service tunnel to transport network packets for a plurality of services. The services are identifiable by virtual local area network (VLAN) identifiers in the packets. The first network device is configured with a single transport interface for the service tunnel and the single transport interface is configured with respective service interfaces for the services. The first network device detects failure of a failed service interface of the service interfaces and outputs, in response to the failure, an EVPN route withdrawal message for the service tunnel that identifies the service corresponding to the failed service interface.

Abstract: The techniques describe packet reordering for packets flowing on a new path in response to a change in internal forwarding paths in a network device. For example, a network device may dynamically change the selection of an internal forwarding path to achieve fabric path optimization (“OFP”) or to ensure optimized load balancing. Packets forwarded on the new path are buffered such that the transmission of packets forwarded on the new path are delayed for a buffering time period of at least the time in which a packet is being sent from the source packet processor to the initial destination packet processor.

Abstract: A device may determine a link aggregation group (LAG) that aggregates links that includes a first group of links that connects the device to a first provider edge (PE) device and a second group of links that connects the device to the second PE device, where the first PE device and the second PE device are on an Ethernet virtual private network (EVPN) and are multi-homed PE devices for the device, and where the first PE device provides a local connection to a customer edge (CE) device for the device. The device may receive a message from the first PE device indicating that the first PE device lacks a connection with the EVPN, and may send, based on the message, traffic intended for the CE device via the first PE device and traffic intended for the EVPN via the second PE device and not the first PE device.

Abstract: The techniques describe forwarding multicast traffic using a multi-level cache in a network device forwarding plane for determining a set of outgoing interfaces of the network device on which to forward the multicast traffic. For example, a multi-level cache is configured to store a multicast identifier of a multicast packet and multicast forwarding information associated with the multicast identifier, such as identification of one or more egress packet processors of the network device to which the multicast packet is to be sent for forwarding to the set of one or more egress network devices, and/or outgoing interfaces of the network device toward each egress network device of the set of one or more egress network devices. The multi-level cache is also configured to store respective multicast identifiers that are to be encapsulated with outgoing multicast packets that are forwarded to the set of one or more egress network devices.

Abstract: Techniques are disclosed for an Ethernet Virtual Private Network (EVPN) Virtual Private Wire Service (VPWS) network with service interface-aware forwarding. In one example, a first network device signals to a second network device, using EVPN route advertisements, a multi-service service tunnel to transport network packets for a plurality of services. The services are identifiable by virtual local area network (VLAN) identifiers in the packets. The first network device is configured with a single transport interface for the service tunnel and the single transport interface is configured with respective service interfaces for the services. The first network device detects failure of a failed service interface of the service interfaces and outputs, in response to the failure, an EVPN route withdrawal message for the service tunnel that identifies the service corresponding to the failed service interface.

Abstract: The techniques describe detecting connectivity failure of an aggregated interface. To monitor connectivity of the aggregated interface, a packet processor of a plurality of packet processors is set as a session master responsible for managing an active forwarding plane connectivity detection session with a peer session master node. The other local packet processors of the virtual network node are selected as session standby nodes that each have a passive forwarding plane connectivity detection session running to the peer session master node. If a session master node goes down (i.e., by link or node failure), one of the local session standby nodes may detect the failure and is set as a new session master node by activating its passive session having the same session parameters.

Abstract: The techniques describe packet reordering for packets flowing on a new path in response to a change in internal forwarding paths in a network device. For example, a network device may dynamically change the selection of an internal forwarding path to achieve fabric path optimization (“OFP”) or to ensure optimized load balancing. Packets forwarded on the new path are buffered such that the transmission of packets forwarded on the new path are delayed for a buffering time period of at least the time in which a packet is being sent from the source packet processor to the initial destination packet processor.