Tag :: Multihoming

EVPN route advertisements carry RD and RT. RD (Route Distinguisher) : prepend to the tenant’s IP Prefix or MAC address to make it globally unique. RT (Route Target) : a BGP extended community used to tag the EVPN route.  The EVPN import policy is chosen to select what is the target tenant VRF is imported from the global EVPN table.

EVPN Multihoming defines a mechanism for Multihoming PEs to quickly signal, to remote PEs, a failure in an Ethernet Segment (ES) connectivity with the use of Ethernet A-D per ES route

Multihoming in EVPN allows a single customer edge (CE) to connect to multiple provider edges (PE or tunnel endpoint). These PE devices are all connected to the same Ethernet-Segment (ES). Multihoming is activated by assigning a unique Ethernet Segment Identifier (ESI) and ES-Import Route Target (RT) which enables all the PEs connected to the same multihomed site to import the Type 4 ES routes

Ethernet VPN (EVPN) networks normally require some measure of redundancy to reduce or eliminate the impact of outages and maintenance. RFC7432 describes four types of route to be exchanged through EVPN, with a built-in multihoming mechanism for redundancy. Prior to EOS 4.22.0F, MLAG was available as a redundancy option for EVPN with VXLAN, but not multihoming. EVPN multihoming is a multi-vendor standards-based redundancy solution that does not require a dedicated peer link and allows for more flexible configurations than MLAG, supporting peering on a per interface level rather than a per device level. It also supports a mass withdrawal mechanism to minimize traffic loss when a link goes down.

[L2 EVPN] and  [Multicast EVPN IRB] solutions allow for the delivery of customer BUM (Broadcast, Unknown unicast