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Provisioning VXLAN EVPN Fabrics with Cisco NDFC: Easy Fabric Workflow Explained

Cisco NDFC (Nexus Dashboard Fabric Controller) is the platform that provisions, manages, and monitors VXLAN BGP EVPN data center fabrics. If you've been using DCNM, heads up — it reaches end-of-support in April 2026. NDFC replaces it entirely, running as a microservices-based application on the Nexus Dashboard platform.

This guide walks through the complete Easy Fabric workflow: from fabric creation to overlay deployment, with the actual NX-OS configs NDFC generates under the hood.


What Changed from DCNM to NDFC?

DCNM was a standalone Java monolith. NDFC is containerized microservices on Nexus Dashboard, sitting alongside Nexus Dashboard Insights (NDI) and Nexus Dashboard Orchestrator (NDO).

Feature DCNM NDFC
Deployment Standalone VM/OVA Service on Nexus Dashboard
Architecture Monolithic Java Microservices, containerized
Fabric types Easy Fabric, VXLAN, classic LAN Same + Campus VXLAN, External
Multi-site Via DCNM Via NDO (separate service)
Assurance Basic monitoring Integrated with NDI
API REST API (limited) Full REST API + Terraform provider
Support status EOL April 2026 Active development

What Catches DCNM Users Off-Guard

  • Navigation changes — NDFC's left-nav structure differs from DCNM's tabbed interface
  • Fabric creation wizard — more parameters exposed upfront, different field ordering
  • Deploy workflow — \"Recalculate and Deploy\" replaces DCNM's \"Deploy\" button with a preview + diff step
  • Integrated topology view — real-time fabric visualization is now built-in

The Easy Fabric Workflow: Step by Step

Easy Fabric is NDFC's flagship feature — it provisions a complete VXLAN BGP EVPN fabric from a single template.

Step 1: Create the Fabric

Navigate to Fabric Controller → LAN → Fabrics → Create Fabric and select \"Data Center VXLAN EVPN.\"

Core parameters:

Parameter Description Typical Value
Fabric Name Unique identifier DC1-VXLAN
BGP ASN BGP AS number 65001
Underlay Protocol IS-IS (recommended) or OSPF IS-IS
Replication Mode Multicast or Ingress Replication Multicast
Multicast Group Subnet PIM ASM group range 239.1.1.0/25
Anycast RP Enable on spines Enabled
Loopback0 IP Range Router IDs 10.2.0.0/22
Loopback1 IP Range VTEP (NVE) source 10.3.0.0/22
Subnet Range P2P inter-switch links 10.4.0.0/22

The template contains hundreds of parameters, but these core settings define the underlay design. NDFC auto-calculates the rest.

Step 2: Discover and Assign Switch Roles

Add switches via seed IP discovery (CDP/LLDP neighbor walk), POAP, or manual add. Then assign roles:

Role Function Typical Platform
Spine Route reflector, underlay/overlay hub Nexus 9500, 9300
Leaf Server-facing, VTEP, gateway Nexus 9300, 9200
Border Leaf External L3 connectivity Nexus 9300
Border Spine Combined spine + external Nexus 9500
Border Gateway Multi-site EVPN gateway Nexus 9300, 9500

NDFC validates role assignments topologically — it won't let you assign a spine role to a switch that only connects to hosts.

Step 3: Deploy the Underlay

Click Recalculate and Deploy. NDFC generates the complete underlay:

  • IS-IS (or OSPF) adjacencies on all spine-leaf links
  • PIM sparse-mode with anycast RP on spines
  • Loopback0 (router ID) and Loopback1 (NVE source)
  • Point-to-point links with /30 or /31 addressing
  • iBGP EVPN with spines as route reflectors

Here's what NDFC generates on a leaf switch:

feature isis
feature pim
feature bgp
feature nv overlay
feature vn-segment-vlan-based

router isis UNDERLAY
  net 49.0001.0100.0200.0003.00
  is-type level-2

interface loopback0
  ip address 10.2.0.3/32
  ip router isis UNDERLAY
  ip pim sparse-mode

interface loopback1
  ip address 10.3.0.3/32
  ip router isis UNDERLAY
  ip pim sparse-mode

interface Ethernet1/49
  description to-spine1
  no switchport
  mtu 9216
  ip address 10.4.0.5/30
  ip router isis UNDERLAY
  ip pim sparse-mode
  no shutdown

router bgp 65001
  router-id 10.2.0.3
  neighbor 10.2.0.1
    remote-as 65001
    update-source loopback0
    address-family l2vpn evpn
      send-community both
      route-reflector-client
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Pro tip: Before deploying, NDFC shows a configuration preview — the actual NX-OS commands. Always review this diff.

Step 4: Create VRFs (L3 VNIs)

Create VRFs for tenant isolation via Fabric → VRFs → Create VRF:

Field Description Example
VRF Name Logical name TENANT-A
VRF ID / VNI L3 VNI 50001
VLAN ID SVI VLAN for L3 VNI 3001
Route Target Auto or manual 65001:50001
Maximum Routes VRF-level route limit 10000

Generated NX-OS:

vrf context TENANT-A
  vni 50001
  rd auto
  address-family ipv4 unicast
    route-target both auto
    route-target both auto evpn
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Step 5: Create Networks (L2 VNIs)

Networks map to VLAN + VNI + anycast gateway via Fabric → Networks → Create Network:

Field Description Example
Network Name Logical name WEB-SERVERS
VLAN ID Local VLAN 100
VNI L2 VNI 30100
Gateway IP Anycast gateway 10.10.100.1/24
VRF Parent VRF TENANT-A

Generated NX-OS:

vlan 100
  vn-segment 30100

interface Vlan100
  vrf member TENANT-A
  ip address 10.10.100.1/24
  fabric forwarding mode anycast-gateway
  no shutdown

interface nve1
  member vni 30100
    mcast-group 239.1.1.1
  member vni 50001 associate-vrf
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Step 6: Verify with CLI

NDFC provides topology views, but CLI verification is essential:

# Verify NVE peers (VXLAN tunnel endpoints)
show nve peers

# Verify BGP EVPN neighbor state
show bgp l2vpn evpn summary

# Verify VXLAN VNI mapping
show nve vni

# Verify MAC learning via EVPN
show l2route evpn mac all

# Verify anycast gateway
show interface vlan 100

# Verify underlay reachability
show isis adjacency
show ip pim neighbor
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Critical Concepts Under the Hood

BGP EVPN Route Types

Route Type Purpose CLI Verification
Type 2 MAC/IP advertisement show bgp l2vpn evpn route-type 2
Type 3 Inclusive multicast (BUM) show bgp l2vpn evpn route-type 3
Type 5 IP prefix route (inter-subnet) show bgp l2vpn evpn route-type 5

Multicast vs. Ingress Replication

  • Multicast (PIM ASM) — BUM traffic flooded via multicast tree. Efficient for large fabrics but requires PIM underlay.
  • Ingress Replication — BUM traffic replicated unicast to each remote VTEP. Simpler but higher bandwidth consumption.

Understand the mcast-group vs ingress-replication protocol bgp commands under interface nve1.

vPC and Host-Facing Configuration

NDFC configures vPC (virtual PortChannel) between leaf pairs for dual-homed servers, including:

  • vPC domain, peer-link, peer-keepalive
  • vPC-specific NVE settings (peer-vtep for Type-5 routes)
  • Orphan port handling

vPC interaction with VXLAN EVPN is one of the most complex topics in DC networking — dual-homed servers, orphan ports, and Type-5 route handling all require deep understanding.


How to Practice

  1. Cisco CML + NDFC VM — Deploy NDFC alongside Nexus 9000v in CML. Requires 32GB+ RAM for NDFC alone.
  2. CLI First, NDFC Second — Build VXLAN EVPN via CLI first to understand what the GUI generates, then layer NDFC on top.
  3. Cisco Practice Labs — Pre-staged lab pods with NDFC are available and closest to the real exam environment.

FAQ

What underlay protocol should I choose?
IS-IS is the default and recommended — it scales better, avoids recursive routing issues, and aligns with SDA underlay design.

Can I still use CLI instead of NDFC?
Yes. NDFC generates standard NX-OS config. Understanding both the GUI workflow and CLI is essential.

What is Easy Fabric?
NDFC's automated provisioning workflow that configures the complete VXLAN BGP EVPN underlay and overlay from a single fabric template.


NDFC is the present and future of Cisco data center fabric management. Mastering both the Easy Fabric GUI workflow and the NX-OS CLI underneath is what separates strong DC engineers from everyone just clicking buttons.

Originally published at firstpasslab.com.


Disclosure: This article was adapted from the original with AI assistance for formatting and editing. Technical content has been expert-reviewed.

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