Configuring The EVPN VXLAN Fabric || Lab-1

In today's topic will discuss the Configuration of VXLAN EVPN fabric and walk through the configurations step by step, Let's start:

Below is our topology we will use during the lab to demonstrate the configuration:

In this lab will go focus on the EVPN VXLAN fabirc to provide Layer-2 extenstion between server-1 and server-2 as shown above. Meanwhile both servers are on different VLAN numbers but on the same subnet, and this what we will see using VXLAN witht he capabilities of EVPN as control plane.

Configuration Building Blocks

Underlay Configuration

1. Configuring Layer-3 reachability between spine and leaf switches, will use OSPF in our Lab

2. Configure Multicast in the underly as it will be used to transmit the traffic in the overlay

Overlay Configuration

1. Provide VNI to VLAN mapping on each leaf switch

2. Configure BGP peering between switches or use spine switches as route-reflector

3. Configure the NVE interface on each switch, which is used as VTEP

4. Map VNI to multicast group for BUM traffic

Configurations

Underlay Configuration

1. Configure OSPF protocol to provide reachability between all switches

### Spine-1, Spine-2, Leaf-1 and Leaf-2 ###

Verification

2. Configure Multicast

• Enable PIM feature and enable it on the pyshical and loopback interfaces as well

### Spine-1, Spine-2, Leaf-1 and Leaf-2 ###

• Configure Spine Switches as rendezvous Point (RP) for redundancy

### Spine-1 and Spine-2 ###

• Advertise the RP address on Underlay IGP protocl and it should be configured and advertised on both Spine switches

### Spine-1 and Spine-2 ###

• Configure RP set on Both Spine Switches

### Spine-1 and Spine-2 ###

• Configure RP address toward the loopback-1 on leaf switches

### Leaf-1 and Leaf-2 ###

Verification

• Verify PIM Neighborship

as we see hereunder that PIM is up and running on leaf-1 and leaf-2 and neighborship is established between leaf and spine switches

• Check RP Status

As we see below, that leaf-1 and leaf-2 has entry for the anycast RP (192.168.254.100) which is the loopback 1 on both spine switches

Overlay Configuration

1. Enable VXLAN and EVPN features

• Enables VLAN-based VXLAN and will allow you to map VLAN o VNI segment

• Enable VXLAN feature

• Enable EVPN on the switch which will allow you to configure an EVPN address family under BGP

2. VNI to VLAN mapping on each leaf switch

3. Configure BGP peering between leaf switches.

• We can configure BGP between Leaf switches directly if the topology is simple like the one above, but i recommend to consider spine switches as route-reflector for scalability and get rid of iBGP limitation

4. Configure the NVE interface on each leaf switch, which is used as VTEP

• Will configure new interface Loopback 1 on each Leaf switches, which will be used as VTEP and ensure that this interface is advertised into OSPF and enable PIM on this interface as well.

Verifivation

• Verify that this new loopback interface is reachable on the underlay

• Create the network virtualization endpoint (NVE) interface.

• Remember that we created interface loopback 1 to be used as a source for the NVE interface

Verifivation

Check NVE interface status, Once it is up you can add VNIs to the interface

5. Map VNI to multicast group for BUM traffic

• Now we need to add the VNI 1000 to NVE interface

• As we will use multicast for BUM traffic, So we need to add multicast group 239.0.0.1 to the VNI interface

Verification

• Verify nve peer status

• Checking VNI status and it is mapped correctly, we can see below that the VNI is up and its type is layer 2. as well as multicast group attached to it.

• Verify Layer 2 routing table

we can see below that we have 2 MAC address entries in each layer 2 routing table, and its Next-Hop, VNI tag.

• Verify multicast routing table

We can see the entries used for BUM traffic

As shown below, the output of Show ibgp l2vpn evpn we noticed the below:

• Server MAC address (5254.0005.871e) is directly connected so we see it with label (l)-means local, and its next hop is the leaf ip itself (192.168.254.111)

• Also we see the remote server MAC address () but in this case it learned via remote leaf vtep (192.168.254.12) from two paths through spine-1 and spine-2

Now we knows how to configure VXLAN EVPN Fabric for bridging traffic between servers in different VLAN, and knows how to configure both underlay and overlay and the functionality for it.

See you in the next articles about Configuring VXLAN EVPN Fabric Lab-2 for Layer 3 VNI