Explains how EVPN E-LAN services use Flex-Algo or SRv6-TE to automate traffic steering and provides deployment, resiliency, configuration, and verification guidance.
EVPNv6 ELAN Layer 2 gateway with automated steering is a capability that
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enables multipoint Layer 2 ELAN services over an SRv6-based network using EVPN BGP signaling,
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automatically steers EVPN ELAN traffic into paths associated with best-effort or Flex-Algorithm locators, and
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combines the advantages of EVPN ELAN services with SRv6 Micro-SIDs for efficient traffic forwarding.
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Feature Name |
Release Information |
Feature Description |
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EVPNv6 ELAN multihoming |
Release 26.1.1 |
Introduced in this release on: Fixed Systems (8200 [ASIC: Q200]); Centralized Systems (8600 [ASIC:Q200]); Modular Systems (8800 [LC ASIC: Q200]) The feature introduces support for an ELAN (P2P) service with multihoming capability over an SRv6 network. The feature supports only the Port-Active multihoming mode. |
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EVPNv6 ELAN single-homing |
Release 26.1.1 |
Introduced in this release on: Fixed Systems (8200 [ASIC: Q200]); Centralized Systems (8600 [ASIC:Q200]); Modular Systems (8800 [LC ASIC: Q200]) EVPNv6 ELAN single-homing provides seamless multipoint-to-multipoint Layer 2 connectivity, enabling efficient communication between multiple customer sites or data centers. |
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EVPNv6 ELAN multihoming |
Release 25.4.1 |
Introduced in this release on: Fixed Systems (8200 [ASIC: P100], 8700 [ASIC: P100, K100], 8010 [ASIC: A100]); Modular Systems (8800 [LC ASIC: P100]) The feature introduces support for an ELAN (P2P) service with multihoming capability over an SRv6 network. Supported multihoming modes:
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EVPNv6 ELAN single-homing |
Release 25.4.1 |
Introduced in this release on: Fixed Systems (8200 [ASIC: P100], 8700 [ASIC: P100, K100], 8010 [ASIC: A100]); Modular Systems (8800 [LC ASIC: P100]) EVPNv6 ELAN single-homing provides seamless multipoint-to-multipoint Layer 2 connectivity, enabling efficient communication between multiple customer sites or data centers. This solution delivers a cost-effective and simplified approach for connecting sites within the same service provider network using EVPN single-homing mode. |
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EVPNv6 ELAN Layer 2 gateway with automated steering to Flex Algo |
Release 25.4.1 |
Introduced in this release on: Fixed Systems (8200 [ASIC: P100], 8700 [ASIC: P100, K100], 8010 [ASIC: A100]); Modular Systems (8800 [LC ASIC: P100]) The feature builds upon EVPN BGP signaling to provide Emulated Local Area Network (ELAN) multipoint-to-multipoint Ethernet services over an SRv6-based network. Automated steering of EVPN ELAN traffic can be enabled for paths associated with a best-effort or Flex-Algorithm locator. This feature combines the benefits of EVPN ELAN service and SRv6 Micro-SIDs. The feature introduces these changes: The segment-routing srv6 option was added to the evi (bridge-domain) command. |
SRv6 behavior for EVPN Layer 2 traffic
You can transport EVPN ELAN bridged unicast and broadcast, unknown unicast, and multicast (BUM) traffic over an SRv6 network in the Micro-SID format.
Relevant SRv6 headend and endpoint definitions include:
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H.Encaps.L2.Red . This headend router operation uses reduced encapsulation of Layer 2 or Ether frames through an SRv6 Policy.
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uDT2U . This endpoint router operation involves traffic decapsulation and unicast MAC Layer 2 table lookup. This is used for the EVPN bridging unicast traffic use case.
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uDT2M . This endpoint router operation involves traffic decapsulation and Layer 2 table flooding. This is used for the EVPN bridging BUM traffic with ESI filtering use case.
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Multihoming . This enables you to connect a customer edge (CE) device to two or more provider edge (PE) devices to provide redundant connectivity. The redundant PE device ensures that there is no traffic disruption when there is a network failure. Following are the types of multihoming:
For more information on SRv6 headend and endpoint behaviors, see the Segment Routing over IPv6 Overview chapter.
Multihoming concepts and modes
Multihoming allows a CE device to connect to two or more PE devices, providing redundant connectivity. This redundant configuration ensures continuous traffic flow even if a network failure occurs.
The multihoming modes are:
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All-Active . In active-active mode, all PEs attached to the Ethernet Segment are allowed to forward traffic to and from that segment.
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Single-Active . In single-active mode, only one PE among a group attached to the Ethernet Segment is allowed to forward traffic to and from that segment, while backup ports are out of service.
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Port-Active . In single-active mode, only a single PE among a group of PEs attached to the particular Ethernet-Segment is allowed to forward traffic to and from that Ethernet Segment; backup ports are Out-of-Service.
For more information about EVPN single-homing, multihoming, and topology concepts, see L2VPN and Ethernet Services Configuration Guide for Cisco 8000 Series Routers.