Help us improve your experience.

Let us know what you think.

Do you have time for a two-minute survey?

 
ON THIS PAGE
 

Symmetric IRB using RT2 (MAC-IP)

This section briefly describes the symmetric integrated and routing bridging with EVPN over VXLAN with Type 2 routes and its configuration on the QFX5220, QFX5230, QFX5240, and QFX5241 Switches.

Overview

The provider edge (PE) devices in an EVPN fabric can handle traffic to and from the attached multihomed end devices by grouping the multihoming links into an EVPN Ethernet segment with an identifier (ESI). The multihoming links participating in the Ethernet segment are configured into a link aggregation group (LAG). Thus, the set of multihomed links is called as an 'ESI LAG' or EZ-LAG feature. This feature provides a simplified configuration statement hierarchy and a built-in commit script that you can use to set up an EVPN multihoming. This feature makes it easy to migrate a multichassis link aggregation group (MC-LAG) topology to a standards-based EVPN-VXLAN multihoming model. For more information about ESI-LAG, see Benefits of using Easy EVPN LAG Configuration.

Configure Symmetric IRB Using RT2

Juniper devices use asymmetric model with EVPN Type 2 routes by default, or you can enable the symmetric model with EVPN Type 2 routes. EVPN Type 2 symmetric routing is supported as follows:

  • In an EVPN-VXLAN, fabric with an edge-routed bridging (ERB) overlay

  • EVPN instances are configured using MAC-VRF routing instances with VLAN-based or VLAN-aware bundle service types (see MAC-VRF Routing Instance Type Overview).

To enable symmetric EVPN Type 2 routing on leaf devices in an EVPN-VXLAN fabric with an ERB overlay.

  1. On the leaf devices that serve as VTEPs, configure the base MAC-VRF EVPN instances, tenant L3 VRF instances, associated VLANs, and corresponding IRB interfaces for your EVPN-VXLAN network.

  2. Configure EVPN Type 5 routing in the EVPN-VXLAN network to establish Layer 3 connectivity between all leaf devices serving as VTEPs.

    In this step, you configure the L3 VRF instances to use EVPN Type 5 routes with a corresponding VNI to advertise the direct next hops for VXLAN traffic. For example:

    The device uses the L3 VRF EVPN Type 5 VNI as the L3 transit VNI for symmetric EVPN Type 2 routing.

  3. Enable symmetric Type 2 routing in the L3 VRF instances using the irb-symmetric-routing vni vni statement at the [edit routing instances name protocols evpn] hierarchy level.

    For example:

    Specify the transit VNI value (l3-vni) as the same VNI you configure in Step 2 when you enable EVPN Type 5 routing for each L3 VRF.

Verify Symmetric IRB Configuration Using RT2

To verify the configuration of symmetric IRB using RT2: