This chapter contains the following topics:
Ethernet Virtual Private Network (EVPN) is a technology that allows Layer 2 traffic to be bridged across an IP network. EVPN instances configured on Provider Edge (PE) routers function as virtual bridges, transporting traffic between Customer Edge (CE) devices at separate locations.
At a basic level, the PE routers exchange information about reachability, encapsulate Layer 2 traffic from CE devices, and forward it across the Layer 3 network. EVPN is the de-facto standard technology in multi-tenant Data Centers (DCs).
VXLAN is a means for segmenting a LAN at a scale required by service providers. With the prevalent use of VXLAN in multi-tenant DCs, the EVPN control plane was adapted for VXLAN tunnels in RFC8365.
The SR Linux EVPN-VXLAN solution supports using Layer 2 Broadcast Domains (BDs) in multi-tenant data centers using EVPN for the control plane and VXLAN as the data plane.
Layer 2 services refers to the infrastructure implemented on SR Linux to support tunneling of Layer 2 traffic across an IP network, overlaying the Layer 2 network on top of the IP network.
To do this, SR Linux uses a network instance of type mac-vrf. The mac-vrf network instance is associated with a network instance of type default or ip-vrf via an Integrated Routing and Bridging (IRB) interface.
Figure 1 shows the relationship between an IRB interface and mac-vrf, and ip-vrf network instance types.
See Layer 2 services infrastructure for information about Layer 2 services on SR Linux, including configuring mac-vrfs, ip-vrfs, and IRB interfaces.
The primary usage for EVPN for VXLAN tunnels (Layer 2) is the extension of a BD in overlay multi-tenant DCs. This kind of topology is illustrated in Figure 2.
SR Linux features that support this topology fall into the following categories:
EVPN for VXLAN tunnels (Layer 2) describes the components of EVPN-VXLAN Layer 2 on SR Linux.
The primary usage for EVPN for VXLAN tunnels (Layer 3) is inter-subnet-forwarding for unicast traffic within the same tenant infrastructure. This kind of topology is illustrated in Figure 3.
SR Linux features that support this topology fall into the following categories:
Other supported features include:
EVPN for VXLAN tunnels (Layer 3) describes the components of EVPN-VXLAN Layer 3 on SR Linux.