Nexus 7000: OTV VLAN Mapping on Overlay interface

Introduction

Beginning with Cisco NX-OS Release 6.2(2), you can map a VLAN on the local site to a VLAN with a different VLAN ID on the remote site. When you map two VLANs with different VLAN IDs across sites, they get mapped to a common VLAN called the transport VLAN. For example, when you map VLAN 1 on Site A to VLAN 2 on Site B, both VLANs are mapped to a transport VLAN. All traffic originating from VLAN 1 on Site A is translated as going from the transport VLAN. All traffic arriving at Site B from the transport VLAN is translated to VLAN 2.

This document provides a configuratione example for accomplishing Vlan mapping across OTV.

There are 2 methods to configure vlan translation across OTV:

1. Vlan translation on trunk port (OTV Internal Interface)

2. Vlan mapping configured on Overlay (currently not supported on F3 modules).

This document will discuss the 2nd method - Vlan mapping configured on Overlay.

The first method is covered in a separate document.

Prerequisites

Requirements

Cisco recommends that you have knowledge of these topics:

• OTV
• Virtual port channel (vPC)

Components Used

• Cisco Nexus 7000 Series Switches with Supervisor 2 Module.
• M2 and F2 linecards. This config should work with other linecards as well except F3. F3 modules currently do not support Vlan mapping on Overlay interface.
• SW version: 6.2.18
• Feature (Vlan translation) support started: 6.2.2

 The information in this document was created from the devices in a specific lab environment.  All of the devices used in this document started with a cleared (default) configuration. If your network is live, make sure that you understand the potential impact of any command.

Configure

Network Diagram

Configurations

SITE-1:

AGG VDC:
interface Vlan100
 no shutdown
 no ip redirects
 ip address 10.1.1.1/24

interface port-channel10
 switchport
 switchport mode trunk
 mtu 9216

OTV VDC
interface Overlay1
 otv join-interface Ethernetx/y
 otv control-group xx.xxx.xx.xx
 otv data-group xx.xxx.xxx.xx
 otv extend-vlan 100                                <+++++++++++++ Extend Local Vlan 100
 otv vlan mapping 100 to 200                        <+++++++++++++ Local Vlan 100 mapped to remote Vlan 200
 no shutdown

SITE-2:

AGG VDC:
interface Vlan200
 no shutdown
 no ip redirects
 ip address 10.1.1.3/24

interface port-channel10
 switchport
 switchport mode trunk
 mtu 9216

OTV VDC:
interface Overlay1
 otv join-interface Ethernetx/y
 otv control-group xx.xxx.xx.xx
 otv data-group xx.xxx.xxx.xx
 otv extend-vlan 200                                      <+++++++++++++ Extend Local Vlan 200. NOTE: No need to map Vlans at this site. 
 no shutdown

Verify

SITE-1:

OTV VDC:
+++++++

N7K-Site1-OTV# sh otv vlan-mapping overlay 1
Original VLAN -> Translated VLAN
--------------------------------
 100         ->      200                  <++++++ Vlan 100 mapped to 200 when traffic is sent/received on Overlay 


N7K-Site1-OTV# sh otv route | inc 8478.ac0c.7b45
 100 8478.ac0c.7b45 1 00:05:14 site port-channel10 <++++++ Local Vlan 100 SVI MAC learned from internal interface

N7K-Site1-OTV# sh otv route | inc 8478.ac0c.7b46
 100 8478.ac0c.7b46 42 00:05:23 overlay N7K-Site2-OTV    <+++++ Remote Vlan 200 SVI MAC learned in Vlan 100 on OTV VDC


SITE-2:

OTV VDC:
++++++++

N7K-Site2-OTV# sh otv vlan-mapping overlay 1
Original VLAN -> Translated VLAN
--------------------------------          <++++++ No need for translation at this site. Traffic is received/sent in Vlan 200

N7K-Site2-OTV# sh otv route | inc 8478.ac0c.7b45
 200 8478.ac0c.7b45 42 00:02:51 overlay N7K-Site1-OTV  <++++ Remote Vlan 100 SVI MAC learned in Vlan 200 in OTV VDC

N7K-Site2-OTV# sh otv route | inc 8478.ac0c.7b46
 200 8478.ac0c.7b46 1 00:10:45 site port-channel10   <+++++ Local Vlan 200 SVI MAC learned from internal interface

 Reference:

OTV Configuration guide