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4.6.5 Fabric Zones Configuration

Document Information

Item Details
Organization Abhavtech.com
Domain abhavtech.com
Version 2.0
Last Updated December 2025

1. Fabric Zones Overview

1.1 Introduction

Fabric Zones provide granular control over IP pool assignment within a fabric site. They allow network administrators to scope IP pools to specific subsets of edge nodes rather than the entire fabric site.

┌─────────────────────────────────────────────────────────────────────┐
│                    Abhavtech.com Fabric Site                        │
│                         Mumbai Campus                               │
├─────────────────────────────────────────────────────────────────────┤
│                                                                     │
│   ┌─────────────────────────────────────┐                          │
│   │         Fabric Zone: Building-A      │                          │
│   │                                      │                          │
│   │  ┌──────────┐  ┌──────────┐        │                          │
│   │  │ MUM-ED-01│  │ MUM-ED-02│        │  IP Pool: 10.100.10.0/24 │
│   │  │ (Edge)   │  │ (Edge)   │        │  VN: VN_CORPORATE        │
│   │  └──────────┘  └──────────┘        │                          │
│   │                                      │                          │
│   │  ┌──────────┐                       │                          │
│   │  │ MUM-EX-01│  (Extended Node)      │                          │
│   │  └──────────┘                       │                          │
│   └─────────────────────────────────────┘                          │
│                                                                     │
│   ┌─────────────────────────────────────┐                          │
│   │         Fabric Zone: Building-B      │                          │
│   │                                      │                          │
│   │  ┌──────────┐  ┌──────────┐        │                          │
│   │  │ MUM-ED-03│  │ MUM-ED-04│        │  IP Pool: 10.100.20.0/24 │
│   │  │ (Edge)   │  │ (Edge)   │        │  VN: VN_CORPORATE        │
│   │  └──────────┘  └──────────┘        │                          │
│   └─────────────────────────────────────┘                          │
│                                                                     │
│   Control Plane: MUM-CP-01, MUM-CP-02 (Site-wide)                  │
│   Border Nodes: MUM-BN-01, MUM-BN-02 (Site-wide)                   │
│                                                                     │
└─────────────────────────────────────────────────────────────────────┘

1.2 Key Concepts

Concept Description
Fabric Site Parent container for all fabric nodes
Fabric Zone Subset of edge nodes within a site
IP Pool Scoping IP pools assigned to zones, not entire site
Inheritance Zones inherit VNs from parent site

1.3 Node Placement Rules

Fabric_Zone_Rules:
  Control_Plane_Nodes:
    - Always at Fabric Site level
    - Cannot be in Fabric Zones

  Border_Nodes:
    - Always at Fabric Site level
    - Cannot be in Fabric Zones

  Edge_Nodes:
    - Added to Fabric Zones
    - Inherit site-level VNs

  Extended_Nodes:
    - Must be in same zone as parent Edge
    - PEN and Classic types supported

  Policy_Extended_Nodes:
    - Must be in same zone as parent Edge
    - Full SGT enforcement capability

2. Abhavtech.com Fabric Zone Design

2.1 Mumbai Campus Zones

Zone Name Building Edge Nodes Extended Nodes IP Pools
MUM-ZONE-BLDG-A Building A MUM-ED-01, MUM-ED-02 MUM-EX-01, MUM-EX-02 10.100.10.0/24, 10.100.11.0/24
MUM-ZONE-BLDG-B Building B MUM-ED-03, MUM-ED-04 MUM-EX-03 10.100.20.0/24, 10.100.21.0/24
MUM-ZONE-DC Data Center MUM-ED-DC-01, MUM-ED-DC-02 None 10.100.100.0/24

2.2 Chennai Campus Zones

Zone Name Building Edge Nodes Extended Nodes IP Pools
CHE-ZONE-MAIN Main Campus CHE-ED-01, CHE-ED-02 CHE-EX-01 10.102.10.0/24
CHE-ZONE-ANNEX Annex Building CHE-ED-03 None 10.102.20.0/24

2.3 Global Site Hierarchy

Abhavtech.com
├── Global
│   ├── APAC
│   │   ├── India
│   │   │   ├── Mumbai (Fabric Site)
│   │   │   │   ├── MUM-ZONE-BLDG-A (Fabric Zone)
│   │   │   │   ├── MUM-ZONE-BLDG-B (Fabric Zone)
│   │   │   │   └── MUM-ZONE-DC (Fabric Zone)
│   │   │   └── Chennai (Fabric Site)
│   │   │       ├── CHE-ZONE-MAIN (Fabric Zone)
│   │   │       └── CHE-ZONE-ANNEX (Fabric Zone)
│   ├── EMEA
│   │   ├── UK
│   │   │   └── London (Fabric Site)
│   │   │       ├── LON-ZONE-CANARY (Fabric Zone)
│   │   │       └── LON-ZONE-CITY (Fabric Zone)
│   │   └── Germany
│   │       └── Frankfurt (Fabric Site)
│   │           └── FRA-ZONE-MAIN (Fabric Zone)
│   └── AMER
│       └── USA
│           ├── New Jersey (Fabric Site)
│           │   ├── NJ-ZONE-CAMPUS (Fabric Zone)
│           │   └── NJ-ZONE-DC (Fabric Zone)
│           └── Dallas (Fabric Site)
│               └── DAL-ZONE-MAIN (Fabric Zone)

3. Catalyst Center Configuration

3.1 Creating Fabric Zones

Step 1: Navigate to Fabric Site

Menu → Provision → Fabric Sites → Select "Mumbai"

Step 2: Add Fabric Zone

Actions → Add Fabric Zone

Zone Configuration:
  Zone Name: MUM-ZONE-BLDG-A
  Description: Mumbai Building A - Floors 1-5

Click "Add"

Step 3: Add Edge Nodes to Zone

Select Zone "MUM-ZONE-BLDG-A"
→ Fabric Infrastructure
→ Add → Select Edge Nodes

Selected Nodes:
  ☑ MUM-ED-01.abhavtech.com
  ☑ MUM-ED-02.abhavtech.com

Click "Add"

3.2 Assigning IP Pools to Zones

Prerequisites: - VN must be assigned to parent Fabric Site first - IP pool must be created in Network Settings

Step 1: Assign VN to Site (if not done)

Fabric Site: Mumbai
→ Host Onboarding
→ Virtual Networks
→ Add: VN_CORPORATE, VN_VOICE, VN_IOT, VN_GUEST

Step 2: Assign IP Pool to Zone

Select Zone: MUM-ZONE-BLDG-A
→ Host Onboarding
→ Add IP Pool

IP Pool Configuration:
  Virtual Network: VN_CORPORATE
  IP Pool: CORP-BLDG-A-POOL (10.100.10.0/24)

  Pool Type: LAN
  Traffic Type: Data
  Scalable Group: Employee-Full (SGT 10)

  DHCP Server: 10.250.1.10 (Infoblox APAC)
  DNS Server: 10.250.1.11 (Infoblox APAC)

Click "Add"

3.3 Zone-Specific IP Pool Matrix

Fabric Zone VN IP Pool VLAN SGT DHCP (Geo) DNS (Geo)
MUM-ZONE-BLDG-A VN_CORPORATE 10.100.10.0/24 Auto 10 10.250.1.10 (APAC) 10.250.1.11 (APAC)
MUM-ZONE-BLDG-A VN_VOICE 10.100.11.0/24 Auto 20 10.250.1.10 (APAC) 10.250.1.11 (APAC)
MUM-ZONE-BLDG-B VN_CORPORATE 10.100.20.0/24 Auto 10 10.250.1.10 (APAC) 10.250.1.11 (APAC)
MUM-ZONE-BLDG-B VN_IOT 10.100.21.0/24 Auto 50 10.250.1.10 (APAC) 10.250.1.11 (APAC)
MUM-ZONE-DC VN_CORPORATE 10.100.100.0/24 Auto 14 10.250.1.10 (APAC) 10.250.1.11 (APAC)

4. Extended Nodes in Fabric Zones

4.1 Extended Node Types

Type Description SGT Enforcement Use Case
Classic Extended Node Basic fabric extension At parent Edge only Legacy/IE switches
Policy Extended Node (PEN) Full TrustSec support On extended node itself Cat 9000 in closets

4.2 Adding Extended Node to Zone

Step 1: Ensure Parent Edge is in Zone

Zone: MUM-ZONE-BLDG-A
Edge Nodes: MUM-ED-01 (parent)

Step 2: Add Extended Node

Select Zone: MUM-ZONE-BLDG-A
→ Fabric Infrastructure
→ Add Extended Node

Extended Node Configuration:
  Device: MUM-EX-01.abhavtech.com
  Parent Edge: MUM-ED-01.abhavtech.com
  Extended Node Type: Policy Extended Node
  Uplink Interface: TenGigabitEthernet1/1/1

Click "Add"

4.3 Policy Extended Node Configuration

! Policy Extended Node - MUM-EX-01
! Automatically configured by Catalyst Center

! TrustSec Configuration
cts role-based enforcement
cts role-based enforcement vlan-list all

! SGACL Download
cts role-based sgt-map 10.100.10.0/24 sgt 10
cts authorization list ABHAVTECH-SGACL

! Uplink to Parent Edge
interface TenGigabitEthernet1/1/1
 description Uplink to MUM-ED-01
 switchport mode trunk
 switchport trunk allowed vlan all
 cts manual
  policy static sgt 2 trusted
!

5. IP Pool Scoping Examples

5.1 Before Fabric Zones (Site-wide Pool)

Fabric Site: Mumbai
├── IP Pool: 10.100.0.0/16 (entire site)
├── Edge Nodes: All 6 edges share same pool
└── Problem: No granular control, large broadcast domain

5.2 After Fabric Zones (Scoped Pools)

Fabric Site: Mumbai
├── Zone: MUM-ZONE-BLDG-A
│   ├── IP Pool: 10.100.10.0/24 (Building A only)
│   ├── Edge Nodes: MUM-ED-01, MUM-ED-02
│   └── Benefit: Isolated broadcast, targeted policy
├── Zone: MUM-ZONE-BLDG-B
│   ├── IP Pool: 10.100.20.0/24 (Building B only)
│   ├── Edge Nodes: MUM-ED-03, MUM-ED-04
│   └── Benefit: Separate address space
└── Zone: MUM-ZONE-DC
    ├── IP Pool: 10.100.100.0/24 (DC only)
    ├── Edge Nodes: MUM-ED-DC-01, MUM-ED-DC-02
    └── Benefit: Server isolation

6. Verification

6.1 Catalyst Center Verification

Provision → Fabric Sites → Mumbai → Fabric Zones

Expected Output:
┌─────────────────┬────────────┬─────────────┬──────────────┐
│ Zone Name       │ Edge Nodes │ Ext Nodes   │ IP Pools     │
├─────────────────┼────────────┼─────────────┼──────────────┤
│ MUM-ZONE-BLDG-A │ 2          │ 2           │ 2            │
│ MUM-ZONE-BLDG-B │ 2          │ 1           │ 2            │
│ MUM-ZONE-DC     │ 2          │ 0           │ 1            │
└─────────────────┴────────────┴─────────────┴──────────────┘

6.2 CLI Verification on Edge Nodes

! Verify LISP database on edge
show lisp instance-id 4097 ipv4 database

! Expected: Only pools assigned to this zone
LISP ETR IPv4 Mapping Database for EID-table vrf VN_CORPORATE
  10.100.10.0/24, locator-set RLOC-SET
    Locator       Pri/Wgt   Source   State
    10.251.1.11    1/50     cfg-intf Up

! Verify on edge in different zone (should NOT see other zone pools)
MUM-ED-03# show lisp instance-id 4097 ipv4 database
  10.100.20.0/24, locator-set RLOC-SET   <-- Building B pool only

7. Best Practices

7.1 Zone Design Guidelines

  1. Zone per Building/Floor: Align zones with physical boundaries
  2. IP Pool Sizing: Size pools for zone capacity + 20% growth
  3. Extended Node Placement: Keep EX in same zone as parent
  4. VN Assignment Order: Site first, then zone IP pools
  5. Naming Convention: <SITE>-ZONE-<BUILDING/FUNCTION>

7.2 Common Mistakes to Avoid

Mistake Impact Correction
Adding Border to Zone Provisioning failure Keep borders at site level
IP pool before VN Pool assignment fails Add VN to site first
EX in different zone than parent Invalid configuration Match EX zone to parent Edge
Overlapping pools IP conflicts Use unique pools per zone

Document Version: 2.0 Abhavtech.com - SD-Access Implementation