Quick Start Guide Overlay Transport Virtualization (OTV)

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Quick Start Guide Overlay Transport Virtualization (OTV)

Architecture & Solutions GroupUS Public Sector Advanced ServicesMark Stinnette, CCIE Data Center #39151

Date 28 August 2013Version 1.2.2


This presentation will provide end-to-end configurations mapped directly to commonly deployed data center architecture topologies. In this cookbook style; quick start guide; configurations are broken down in an animated step by step process to a complete end-to-end good clean configuration based on Cisco best practices and strong recommendations. Each QSG will contain set the stage content, technology component definitions, recommended best practices, and more importantly different scenario data center topologies mapped directly to complete end-to-end configurations. This QSG is geared for network engineers, network operators, and data center architects to allow them to quickly and effectively deploy these technologies in their data center infrastructure based on proven commonly deployed designs.

This Quick Start Guide (QSG) is a Cookbook style guide to Deploying Data Center technologies with end-to-end configurations for several commonly deployed architectures.


Geographically dispersed data centers provide added application resiliency and workload allocation flexibility. To this end, the network must provide Layer 2, Layer 3 and storage connectivity between data centers. Connectivity must be provided without compromising the autonomy of data centers or the stability of the overall network. OTV provides an operationally optimized solution for the extension of Layer 2 connectivity across any transport. OTV is therefore critical to the effective deployment of distributed data centers to support application availability and flexible workload mobility.

OTV is a "MAC address in IP" technique for supporting Layer 2 VPNs to extend LANs over any transport. The transport can be Layer 2 based, Layer 3 based, IP switched, label switched, or anything else as long as it can carry IP packets. By using the principles of MAC routing, OTV provides an overlay that enables Layer 2 connectivity between separate Layer 2 domains while keeping these domains independent and preserving the fault-isolation, resiliency, and load-balancing benefits of an IP-based interconnection.

Overlay Transport Virtualization (OTV) provides the following benefits:• Scalability

Extends Layer 2 LANs over any network that supports IP (Transport agnostic)Designed to scale across multiple data centers

• SimplicitySupports transparent deployment over existing network without redesignRequires minimal configuration commands

• ResiliencyPreserves existing Layer 3 failure boundariesIncludes built-in loop preventionFailure boundary preservation and site independence preservation (failover isolation between data centers)

• EfficiencyOptimized available bandwidth, by using equal-cost multi-pathing and optimal multicast replicationMultipoint connectivityFast failover

• Virtual Machine Mobility

OTV ConfigurationBenefits Overview


Additional benefits of using OTV for Layer 2 extension:

• No need for Ethernet over Multiprotocol Label Switching (EoMPLS) or Virtual Private LAN Services (VPLS) deployment for Layer 2 extensions

• Use any network transport that supports IP

• Provision of Layer 2 and Layer 3 connectivity using the same dark fiber connections

• Native Spanning Tree Protocol (STP) isolation: No need to explicitly configure Bridge Data Protocol Unit (BPDU) filtering

• Native unknown unicast flooding isolation:Unknown unicast not sent to the overlay

• Address Resolution Protocol (ARP) optimization with the OTV ARP cache

• Simplified provisioning of First Hop Redundancy Protocol (FHRP) isolation

• Simplified addition of sites

OTV ConfigurationBenefits Overview


Most Commonly Deployed No Network Redesign or Re-Cabling Join Interface connects back through the VDC

that has the SVIs on them Separate OTV VDC or Appliance Switch

Dedicated Uplink for DCI Join Interface has a dedicated link out to the

DCI transport (Core or WAN Edge) Separate OTV VDC or Appliance Switch

OTV On a StickInline OTV

OTV ConfigurationCommonly Deployed Designs :: Aggregation Layer

L3 & Join Interfaces

L2 Internal Interfaces


vPC Domain(vPC or vPC+ Supported)

Join Interfaces Point-to-Point Layer 3

interfaceM-Series Line Cards Only

OTV delivers Layer 2 extensions over any type of transport infrastructure

OTV ConfigurationTerminology & Components

OTV Edge DevicePerforms OTV Functions

Internal InterfacesRegular Layer 2 & Carries VLANs extended over OTV

Peer-Link

M-Series Line Cards SupportedF1 & F2E Line Cards Supported in 6.2(2)

Multicast or UnicastTransports Supported

Authoritative Edge Device (AED )Even VLANs

SVI Separation on the Aggregation VDC

Authoritative Edge Device (AED )

Odd VLANs

OTV Overlay Interface


OTV encapsulates packets into an IP header and where it sets the Don't Fragment (DF) bit for all OTV control and data packets crossing the transport network. The encapsulation adds 42 bytes to the original IP maximum transition unit (MTU) size. So it is a best practice to configure the join interface and all Layer 3 interfaces that face the IP core between the OTV edge devices with the max possible MTU size supported by the transport.

Filtering FHRP in both data centers on the OTV VDC is required to allow for existence of the same default gateway in different locations thus optimizing the outbound traffic flows (server to client direction)

OTV ConfigurationTerminology & Components

Site ID & Site VLAN are Deployed on Both OTV Edge DevicesSite Identifier ::Use same Site ID within a single data centerUse unique Site ID between different data centersSite VLAN ::Use same Site VLAN between different data centers (not mandatory) Site VLAN is active on internal interfaces but don’t extend Site VLANThe Site VLAN should be a dedicated VLAN

WEST DC EAST DC

HSRP Active HSRP StandbyHSRP Active HSRP Standby

Filter HSRPFilter HSRPFilter HSRPFilter HSRP

Site ID 1

Site VLAN 99

Site ID 2

Site VLAN 99


Layer 3 Interface (Towards Routed Core)

interface ethernet x/ymtu 9216ip address x.x.x.x/30ip router ospf 1 area 0ip ospf network point-to-point ip pim sparse-mode

OTV Join Interfaces interface ethernet x/y

mtu 9216ip address x.x.x.x/30ip router ospf 1 area 0ip ospf network point-to-point ip igmp version 3

OTV ConfigurationTerminology & Components :: Layer 2 & Layer 3 Features

Layer 3 Interface (Towards OTV Join)

interface ethernet x/zmtu 9216ip address x.x.x.x/30ip router ospf 1 area 0ip ospf network point-to-point ip pim sparse-modeip igmp version 3

Aggregation Switch :: Enable PIMfeature pimip pim rp-address x.x.x.x group-list 224.0.0.0/4

ip pim ssm range 232.0.0.0/8

Aggregation Internal Interfaces interface port-channel x

switchportswitchport mode trunkswitchport trunk allowed vlan yvpc x

interface ethernet x/ychannel-group x force mode active

Must enable Site VLAN [x] on trunk

towards the Aggregation Switch[make vlan active]

OTV Internal Interfaces interface port-channel x

switchportswitchport mode trunkswitchport trunk allowed vlan x, y

interface ethernet x/y - zchannel-group x force mode active


Feature OverviewEdge Device The OTV Edge Devices performs OTV functions, multiple OTV Edge Devices can exist at each site. OTV

requires the Transport Services (TRS) license. If you create the OTV Edge Device in a non default VDC; it requires the Advanced Services license.

Internal Interfaces Internal interfaces are the site facing interfaces of the Edge device; carrying VLANs extended through OTV. They are regular Layer 2 interfaces, switch ort mode trunk, and typically port channels in a vPC. No OTV configuration is required on these interfaces.

Join Interfaces Join interfaces are one of the uplink of the Edge device; they are Layer 3 point-to-point routed interfaces (physical interface, port channel, or sub-interface). Its used to physically ‘join’ the Overlay network. No OTV specific configuration required.

Overlay Interface Virtual interface is where most of the OTV configuration happens, logical multi-access multicast-capable interface, encapsulates Layer 2 frames in IP unicast or multicast.

Authoritative Edge Device (AED)

The AED is responsible for MAC address advertisement for its VLANs; forwarding its VLANs traffic inside and outside the site. The extended VLANs are split across the AEDs (even & odd) in OTV multi-homing.

Site VLAN The OTV Site VLAN is used to discover OTV neighbor edge devices in same local site.

Site Identifier Same site Edge devices must use a common unique Site ID. Site ID is included in the control plane; an overlay will not come up until a Site ID is configured; and should be on all local OTV Edge devices.

MTU Join interfaces and neighboring Core interfaces need to have MTU of ≥ 1542 (hard requirement). Best practice to the max possible MTU size supported by the transport

FHRP Isolation Filtering FHRP messages across the OTV Overlay allows to provide the same active default gateway in each data center site. Note, in future releases OTV will offer a simple command to enable these filtering capabilities.

SVI Separation OTV currently enforces SVI separation for the VLANs being extended across the OTV link, meaning OTV is usually in its own VDC for OTV functions and have SVIs in another Aggregation VDC.

OTV ConfigurationAdditional Features, Terminology, & Components


Feature OverviewOTV Requirements Nexus 7000 Series or ASR routers. LAN ADVANCED SERVICES (VDC) license & TRANSPORT

SERVICES (OTV/LISP) license. An M-Series line card is required in the OTV VDC for OTV functions.

Multicast Transport Multicast transport (OTV Control Plane) is ideal for connecting a higher number of sites. OTV Neighbor relationships are built over a multicast enabled core / transport infrastructure. All OTV edge devices can be configured to join a specific ASM (Any Source Multicast) group where they simultaneously play the role of receiver and source. Edge devices join a multicast group; adjacencies are maintained over that multicast group and a single update reaches all neighbors.

Unicast Transport Supported since NX-OS release 5.2. Unicast-only transport (OTV Control Plane) is ideal for connecting a small number of sites. Requires the adjacency server. Each OTV devices would need to create multiple copies of each control plane packet and unicast them to each remote OTV device part of the same logical overlay.

Adjacency Server Used in OTV Unicast mode; usually enabled on an OTV Edge device; can have a primary and secondary; and all other OTV Edge client devices are configured with the address of the adjacency server. The goal is to be able to communicate with all the remote OTV devices, each OTV node needs to know a list of neighbors to replicate the control packets to. Rather than statically configuring in each OTV node the list of all neighbors, a simple dynamic means is used to provide this information; this adjacency server.

OTV Extend VLAN Enables OTV advertisements for those VLANs. OTV will not forward Layer 2 packets for VLANs not in the extended VLAN range for the overlay interface. Assign a VLAN to only one overlay interface.

OTV Authentication OTV supports authentication of Hello messages along with authentication of PDUs.

Dual Homed OTV Edge Devices

Leverage vPC or vPC+ for dual homed OTV Edge devices. The concept of the AED role along with the site vlan allows multi-homing OTV Edge devices.



Feature OverviewSelective Unicast Flooding

In 6.2(2); some applications rely on unknown unicast frames; so selective unicast flooding can be enabled on a per mac address per vlan to accommodate silent or uni-directional hosts. OTV default behavior is no unknown unicast forwarding. Command used: otv flood mac [xxxx.yyyy.zzzz] vlan [#]

Dedicated Data Broadcast Forwarding

In 6.2(2); Dedicated broadcast group is a configurable option; useful for QoS purposes. A dedicated multicast group can be configured for all broadcast transmission in an OTV overlay that utilizes multicast transmission on the underlying OTV network. By default, the broadcast and control traffic will share the same multicast group address. The broadcast group needs to be configured on all OTV Edge devices connected to the OTV overlay network.

Source Interface with Loopback

In 6.2(2); Logical interfaces as Join Interfaces; Loopback to guarantee interfaces is up/up. An OTV Edge device can be configured to use a loopback interface as the join-interface for an OTV overlay to increase availability. This feature requires the OTV Edge device to participate in the core PIM multicast domain to support multiple paths. Prior to this feature only single homed Ethernet and port channel interface options were available.

OTV VLAN Translation In 6.2(2); VLAN translation allows OTV to map a local VLAN (in DC 1) to a remote VLAN (in DC 2). In previous NX-OS releases, the extended VLANs had to be identical in each site (ie. X to X). With the VLAN mapping feature, VLANs can be translated, so they can be different in each site (ie. X to Y to Z) providing more flexible deployment options. Both multicast and unicast enabled IP core networks are supported. VLAN mappings have a one-to-one relationship.



OTV ConfigurationSupported Line Card Topologies :: NX-OS 6.1 and Prior Releases

• OTV VDC must use only M-Series ports for both Internal and Join Interfaces[M1-48, M1-32, M1-08, M2-Series]

• OTV VDC Types (M-only)• Aggregation VDC Types (M-only, M1-F1 or F2/F2E)

Aggregation VDC


OTV ConfigurationSupported Line Card Topologies :: NX-OS 6.2 and Later Releases

• OTV VDC Join Interfaces must use only M-Series ports[M1-48, M1-32, M1-08, M2-Series]

• OTV VDC Internal Interfaces can use M-Series, F1 and F2E ports (F1 and F2E must be in Layer 2 proxy mode)

• OTV VDC Types (M-only, M1-F1, M1-F2E)• Aggregation VDC Types (M-only, M1-F1, M1-F2E, F2, F2E, F2F2E)

Aggregation VDC


Physical View – Connectivity Map

Layer 3 routed point-to-point interfaces. Will be using OSPF as the routing protocol.

Layer 2 interfaces. The Aggregation VDC connects through vPC to the OTV VDC.

OTV ConfigurationQuick Start Guide Assumptions

OTV Characteristics 2-wide 7k Aggregation VDC Multi-homed OTV VDC Multicast enabled transport Extend VLAN 10


[Admin / Default VDC]

no vdc combined-hostname

vdc AGG-1 vdc AGG-1 limit-resource module-type m1 f1 m1xl m2xl cpu-share 5 allocate interface Ethernet [….]

vdc OTV-1 vdc OTV-1 limit-resource module-type m1 m1xl m2xl cpu-share 5 allocate interface Ethernet [….]

[Admin / Default VDC] no vdc combined-hostname

vdc AGG-2 vdc AGG-2 limit-resource module-type m1 f1 m1xl m2xl cpu-share 5 allocate interface Ethernet [….]

vdc OTV-2 vdc OTV-2 limit-resource module-type m1 m1xl m2xl cpu-share 5 allocate interface Ethernet [….]

OTV ConfigurationCreate Aggregation & OTV VDCs

Allocate the Interfaces to appropriate VDC role accordingly

Verify the Nexus 7000 has the proper licenses to support OTV and VDC.

OTV requires the Transport Services licenseVDC requires the Advanced Services license

install license bootflash:///lan_advanced_services_pkg.licinstall license bootflash:///lan_transport_services_pkg.lic

show license usage

Step 1 :: install | validate licensesStep 2 :: create aggregation VDCStep 3 :: create OTV VDC

Perform Configuration Steps at Both DC Sites (East & West)


feature lacpfeature vpc

vlan 10-20

spanning-tree pathcost method longspanning-tree port type edge bpduguard defaultspanning-tree port type edge bpdufilter defaultno spanning-tree loopguard default

spanning-tree vlan 10-20 priority 0spanning-tree pseudo-information vlan 10-20 root priority 4096 vlan 1-10 designated priority 8192 vlan 11-20 designated priority 16384

vpc domain 1 role priority 1 system-priority 4096 peer-keepalive destination [….] source [….] vrf management peer-switch peer-gateway auto-recovery auto-recovery reload-delay delay restore 30 ip arp synchronize

interface port-channel 2 switchport switchport mode trunk switchport trunk allowed vlan 10-20 spanning-tree port type network vpc peer-link interface e3/1 , e4/1 channel-group 2 force mode active

feature lacpfeature vpc

vlan 10-20

spanning-tree pathcost method longspanning-tree port type edge bpduguard defaultspanning-tree port type edge bpdufilter defaultno spanning-tree loopguard default

spanning-tree vlan 10-20 priority 0spanning-tree pseudo-information vlan 10-20 root priority 4096 vlan 1-10 designated priority 16384 vlan 11-20 designated priority 8192

vpc domain 1 role priority 2 system-priority 4096 peer-keepalive destination [….] source [….] vrf management peer-switch peer-gateway auto-recovery auto-recovery reload-delay delay restore 30 ip arp synchronize

interface port-channel 2 switchport switchport mode trunk switchport trunk allowed vlan 10-20 spanning-tree port type network vpc peer-link interface e3/1 , e4/1 channel-group 2 force mode activeSee QSG :: vPC for more details …

OTV ConfigurationConfigure Aggregation VDC :: Layer 2 vPC (Option)



feature lacpfeature vpcinstall feature-set fabricpathfeature-set fabricpath

vlan 10-20mode fabricpath

fabricpath switch-id 10

fabricpath domain default root-priority 255

spanning-tree pseudo-information vlan 10-20 root priority 0

vpc domain 1 role priority 1 system-priority 4096 peer-keepalive destination [….] source [….] vrf management peer-gateway auto-recovery auto-recovery reload-delay delay restore 30 ip arp synchronize fabricpath switch-id 1000

interface port-channel 2 switchport mode fabricpath vpc peer-link interface e3/1 , e4/1 channel-group 2 force mode active

feature lacpfeature vpcinstall feature-set fabricpathfeature-set fabricpath

vlan 10-20 mode fabricpath

fabricpath switch-id 11

fabricpath domain default root-priority 254

spanning-tree pseudo-information vlan 10-20 root priority 0

vpc domain 1 role priority 2 system-priority 4096 peer-keepalive destination [….] source [….] vrf management peer-gateway auto-recovery auto-recovery reload-delay delay restore 30 ip arp synchronize fabricpath switch-id 1000

interface port-channel 2 switchport mode fabricpath vpc peer-link interface e3/1 , e4/1 channel-group 2 force mode activeSee QSG :: FabricPath for more details …

OTV ConfigurationConfigure Aggregation VDC :: Layer 2 FabricPath vPC+ (Option)

Default / Admin VDC Only

Default / Admin VDC Only



feature ospffeature interface-vlanfeature hsrp

vlan 10 – 20

interface loopback0 ip address [….]/32

router ospf 1 router-id [….] log-adjacency-changes detail auto-cost reference-bandwidth 100Gbps

interface e1/1 ip address [….]/30 ip router ospf 1 area 0.0.0.0 ip ospf network point-to-point

interface e1/10 ip address [….]/30 ip router ospf 1 area 0.0.0.0 ip ospf network point-to-point interface vlan 10 ip address 10.10.10.2/24 no ip redirects ip router ospf 1 area 0.0.0.0 ip ospf passive-interface hsrp 1 preempt priority 110 ip 10.10.10.1

feature ospffeature interface-vlanfeature hsrp

vlan 10 – 20



interface e1/1 ip address [….]/30 ip router ospf 1 area 0.0.0.0 ip ospf network point-to-point

interface e1/10 ip address [….]/30 ip router ospf 1 area 0.0.0.0 ip ospf network point-to-point interface vlan 10 ip address 10.10.10.3/24 no ip redirects ip router ospf 1 area 0.0.0.0 ip ospf passive-interface hsrp 1 preempt ip 10.10.10.1

OTV ConfigurationConfigure Aggregation VDC :: Layer 3 Infrastructure

Allocate the following accordingly :: IP addressing OSPF areas SVIs & HSRP Groups



feature ospffeature lacpfeature vpc

interface e 1/2 ip address [….] / 30 ip router ospf 1 area 0.0.0.0 ip ospf network point-to-point

interface port-channel 10 switchport switchport mode trunk switchport trunk allowed vlan 10 vpc 10


interface e5/1 channel-group 10 force mode active








OTV ConfigurationConfigure OTV :: Layer 2 & Layer 3 Infrastructure @ Aggregation

Step 1 :: configure L3 link towards OTV Join InterfaceStep 2 :: configure L2 vPC towards OTV Internal Interface



OTV ConfigurationConfigure OTV :: Layer 2 & Layer 3 Infrastructure @ OTV VDC

Step 1 :: configure OTV Join InterfacesStep 2 :: configure OTV Internal InterfacesStep 3 :: create vlan to extend


feature ospffeature lacp

vlan 10

spanning-tree vlan 10 priority 32768




interface port-channel 10 switchport switchport mode trunk switchport trunk allowed vlan 10

interface e2/1, e2/2 channel-group 10 force mode active

feature ospffeature lacp

vlan 10

spanning-tree vlan 10 priority 32768







OTV ConfigurationConfigure OTV :: Enable Jumbo MTU

Step 1 :: increase MTU on Join InterfacesStep 2 :: increase MTU on all Layer 3 Interfaces



vlan 10

interface e 1/9 mtu 9216 ip address [….] / 30 ip router ospf 1 area 0.0.0.0 ip ospf network point-to-point


vlan 10



vlan 10 – 20


interface e1/10 mtu 9216 ip address [….]/30 ip router ospf 1 area 0.0.0.0 ip ospf network point-to-point



vlan 10 – 20





OTV ConfigurationConfigure OTV :: Enable Required Multicast

Step 1 :: enable PIM Step 2 :: configure PIM sparse mode [AGG VDC]

(on all intra & inter data center Layer 3 links)Step 3 :: configure IGMP v3 [AGG & OTV VDC]

(join interfaces only)Step 4 :: configure Rendezvous Point (RP) Step 5 :: configure Source-Specific Multicast (SSM)


interface e 1/9 mtu 9216 ip address [….] / 30 ip router ospf 1 area 0.0.0.0 ip ospf network point-to-point ip igmp version 3


feature ospffeature lacpfeature vpcfeature pim

ip pim rp-address [x.x.x.x] group-list 224.0.0.0/4 ip pim ssm range 232.0.0.0/8

interface e1/1 mtu 9216 ip address [….]/30 ip router ospf 1 area 0.0.0.0 ip ospf network point-to-point ip pim sparse-mode

interface e 1/2 mtu 9216 ip address [….] / 30 ip router ospf 1 area 0.0.0.0 ip ospf network point-to-point ip pim sparse-mode ip igmp version 3


feature ospffeature lacpfeature vpcfeature pim

ip pim rp-address [x.x.x.x] group-list 224.0.0.0/4 ip pim ssm range 232.0.0.0/8


interface e 1/2 mtu 9216 ip address [….] / 30 ip router ospf 1 area 0.0.0.0 ip ospf network point-to-point ip pim sparse-mode ip igmp version 3



OTV ConfigurationFinish OTV Configuration :: Overlay, Site-ID, Site-VLAN

feature otv

vlan 10

otv site-vlan 99otv site-identifier 0000.0000.0002

interface Overlay 1 otv join-interface ethernet 1/9 otv control-group 239.1.1.1 otv data-group 232.1.1.0/24 otv extend-vlan 10


feature otv

vlan 10


interface Overlay 1 otv join-interface ethernet 1/9 otv control-group 239.1.1.1 otv data-group 232.1.1.0/24 otv extend-vlan 10 interface port-channel 10 switchport switchport mode trunk switchport trunk allowed vlan 10

feature otv

vlan 10





feature otv

vlan 10





Site ID 1

Site VLAN 99

Site ID 2

Site VLAN 99

Step 1 :: enable OTV featureStep 2 :: configure site-vlanStep 3 :: enable site-vlan on L2 trunks (make vlan active)Step 4 :: configure site-identifier Step 5 :: configure OTV Overlay Interface

Site ID 1

Site VLAN 99

Site ID 2

Site VLAN 99



, 99

, 99

, 99

, 99

, 99

, 99

, 99

, 99

OTV Characteristics 2-wide 7k Aggregation VDC Multi-homed OTV VDC Multicast enabled transport Extend VLAN 10


OTV ConfigurationOTV Configuration

The Layer 2 links are known as internal interfaces and are used by the OTV edge device to learn the MAC addresses of the site and forward Layer 2 traffic across the sites for the extended VLANs.

The Layer 3 link is known as the join interface, which OTV uses to perform IP-based virtualization to send and receive overlay traffic between sites. The IP address of this interface is used to advertise reachability of a MAC addresses present in the site. There is one Join interface per OTV Overlay; however, if multiple Layer 3 interfaces are present on the OTV edge device, the unicast extended traffic can get routed over any of these links

OTV encapsulates packets into an IP header and where it sets the Don't Fragment (DF) bit for all OTV control and data packets crossing the transport network. The encapsulation adds 42 bytes to the original IP maximum transition unit (MTU) size. So it is a best practice to configure the join interface and all Layer 3 interfaces that face the IP core between the OTV edge devices with the max possible MTU size supported by the transport.

OTV uses site VLAN to allow multiple OTV edge devices within the site to talk to each other and determine the AED for the OTV-extended VLANs. It is a best practice to use a dedicated VLAN as site VLAN. The site VLAN should not be extended and should be carried down to the aggregation layer across the VPC peer link.

Site ID 1

Site VLAN 99

NOTES

• The OTV edge device is also configured with the overlay interface, which is associated with the join interface to provide connectivity to the physical transport network. The overlay interface is used by OTV to send and receive Layer 2 frames encapsulated in IP packets. From the perspective of MAC-based forwarding on the site, the overlay interface is simply another bridged interface. However, no Spanning Tree Protocol packets or unknown unicast packets are forwarded over the overlay interface.

• Note: The overlay interface does not come up until you configure a multicast group address and the site-VLAN has at least an active port on the device.

• A VLAN is not advertised on the overlay network; therefore, forwarding cannot occur over the overlay network unless the VLANs are explicitly extended. Once the VLAN is extended, the OTV edge device will begin advertising locally learned MAC addresses on the overlay network.

• Key advantages of using multicast is that it allows optimal multicast traffic replication to multiple sites and avoids head-end replication that leads to suboptimal bandwidth utilization.

• When sites are multihomed with OTV EDs, separation is achieved by electing an authoritative edge device (AED) for each VLAN in the same site (site-id), which is the only device that can forward the traffic for the extended VLAN inside and outside the data center. The extended VLANs are split in odd and even and automatically assigned to the site's edge devices.

• The multicast control group identifies the overlay; two different overlays must have two different multicast control groups. The control group is used for neighbor discovery and to exchange MAC address reachability. The data group however is an SSM (Source Specific Group) group range, which is used to carry multicast data traffic generated by the sites

• In the aggregation layer, Protocol Independent Multicast (PIM) is configured on all intra- and inter-data-center Layer 3 links to allow multicast states to be built in the core network.

• Since PIM sparse mode requires a rendezvous point (RP) to build a multicast tree, one of the aggregation switches in each data center is used as an RP. Local RP allows both local sources and receivers to join local RP rather than having to go to different data center to reach an RP in order to build a shared tree. For more information about MSDP and Anycast features of multicast, visit: http://www.cisco.com/en/US/docs/ios/solutions_docs/ip_multicast/White_papers/anycast.html

http://www.cisco.com/en/US/docs/ios/solutions_docs/ip_multicast/White_papers/anycast.html


OTV ConfigurationOTV Configuration :: Unicast-Only Mode

feature otv

vlan 10, 99


interface Overlay 1 otv join-interface ethernet 1/9 otv use-adjacency-server [x] [y] unicast-only otv extend-vlan 10

interface e 1/9 mtu 9216 ip address [z] / 30 ip router ospf 1 area 0.0.0.0 ip ospf network point-to-point

feature otv

vlan 10, 99



interface e 1/9 mtu 9216 ip address [w] / 30 ip router ospf 1 area 0.0.0.0 ip ospf network point-to-point

feature otv

vlan 10, 99


interface Overlay 1 otv join-interface ethernet 1/9 otv adjacency-server unicast-only otv extend-vlan 10

interface e 1/9 mtu 9216 ip address [x] / 30 ip router ospf 1 area 0.0.0.0 ip ospf network point-to-point

feature otv

vlan 10, 99


interface Overlay 1 otv join-interface ethernet 1/9 otv adjacency-server unicast-only otv use-adjacency-server [x] unicast-only otv extend-vlan 10

interface e 1/9 mtu 9216 ip address [y] / 30 ip router ospf 1 area 0.0.0.0 ip ospf network point-to-point

Site ID 1

Site VLAN 99

Site ID 2

Site VLAN 99

Step 1 :: enable OTVStep 2 :: configure site-vlan, site-id, Overlay InterfaceStep 3 :: define role of adjacency server [primary]Step 4 :: define role of adjacency server [secondary]Step 5 :: define all other edge devices as clients

Site ID 1

Site VLAN 99

Site ID 2

Site VLAN 99

Primary Adjacency Server Secondary Adjacency Server

Assume :: enable site-vlan on L2 trunks (make vlan active)

interface port-channel 10 switchport switchport mode trunk switchport trunk allowed vlan 10, 99

Primary Adjacency Server :: Join Interface [x]Secondary Adjacency Server :: Join Interface [y]


OTV ConfigurationOTV Configuration :: Unicast-Only Mode

feature otv

vlan 10, 99



interface e 1/9 mtu 9216 ip address [w] / 30 ip router ospf 1 area 0.0.0.0 ip ospf network point-to-point

feature otv

vlan 10, 99


interface Overlay 1 otv join-interface ethernet 1/9 otv adjacency-server unicast-only otv extend-vlan 10

interface e 1/9 mtu 9216 ip address [x] / 30 ip router ospf 1 area 0.0.0.0 ip ospf network point-to-point

feature otv

vlan 10, 99


interface Overlay 1 otv join-interface ethernet 1/9 otv adjacency-server unicast-only otv use-adjacency-server [x] unicast-only otv extend-vlan 10

interface e 1/9 mtu 9216 ip address [y] / 30 ip router ospf 1 area 0.0.0.0 ip ospf network point-to-point

Primary Adjacency Server Secondary Adjacency Server

Primary Adjacency Server :: Join Interface [x]Secondary Adjacency Server :: Join Interface [y]

Two pieces of configuration are required to deploy OTV across a unicast-only transport infrastructure: first, it is required to define the role of Adjacency Server; whereas the other piece of configuration is required in each OTV edge device not acting as an Adjacency Server (i.e acting as a client). All client OTV edge devices are configured with the address of the Adjacency Server. All other adjacency addresses are discovered dynamically. Thereby, when a new site is added, only the OTV edge devices for the new site need to be configured with the Adjacency Server addresses. No other sites need additional configuration.

The recommendation is usually to deploy a redundant pair of Adjacency Servers in separate DC sites.

The configuration on the Primary Adjacency Server is very simple and limited to enable AS functionality (otv adjacency-server command). The same command is also required on the Secondary Adjacency Server device, but also needs to point to the Primary AS (leveraging the otv use-adjacency-server command). Finally, the generic OTV Edge Device must be configured to use both the Primary and Secondary Adjacency Servers. The sequence of adjacency server address in the configuration determine primary or secondary adjacency server role. This order is relevant since an OTV edge device will always use the OTV neighbor-list (oNL) provided by the Primary Adjacency Server, unless it detects that specific device is not available anymore (control plane Hellos are always exchanged as keepalives between each OTV device and the Adjacency Servers).

NOTES


ip access-list ALL_IPs 10 permit ip any any mac access-list ALL_MACs 10 permit any any ip access-list HSRP_IP 10 permit udp any 224.0.0.2/32 eq 1985 20 permit udp any 224.0.0.102/32 eq 1985 mac access-list HSRP_VMAC 10 permit 0000.0c07.ac00 0000.0000.00ff any 20 permit 0000.0c9f.f000 0000.0000.0fff any arp access-list HSRP_VMAC_ARP 10 deny ip any mac 0000.0c07.ac00 ffff.ffff.ff00 20 deny ip any mac 0000.0c9f.f000 ffff.ffff.f000 30 permit ip any mac any

feature dhcp ip arp inspection filter HSRP_VMAC_ARP vlan 10

vlan access-map HSRP_Localization 10 match mac address HSRP_VMAC match ip address HSRP_IP action drop vlan access-map HSRP_Localization 20 match mac address ALL_MACs match ip address ALL_IPs action forward

vlan filter HSRP_Localization vlan-list 10

mac-list OTV_HSRP_VMAC_deny seq 10 deny 0000.0c07.ac00 ffff.ffff.ff00 mac-list OTV_HSRP_VMAC_deny seq 11 deny 0000.0c9f.f000 ffff.ffff.f000 mac-list OTV_HSRP_VMAC_deny seq 20 permit 0000.0000.0000 0000.0000.0000

route-map OTV_HSRP_filter permit 10 match mac-list OTV_HSRP_VMAC_deny

feature otv

vlan 10, 99



otv-isis default vpn Overlay1 redistribute filter route-map OTV_HSRP_filter

Step 1 :: create OTV HSRP access-lists (VACL)Step 2 :: create OTV HSRP localization filters

Filter out HSRP v1 and v2Filter out Gratuitous ARP

Step 3 :: create route-map to prevent advertisements of HSRP VMACs

OTV ConfigurationOTV Configuration :: HSRP Filtering

The filtering of FHRP messages across the overlay is a critical functionality to be enabled, because it allows applying the same FHRP configuration in different sites. The end result is that the same default gateway is available (i.e. characterized by the same virtual IP and virtual MAC addresses) in each data center. This capability optimizes the outbound traffic flows (server to client direction); but this does not solve the mechanism to control and improve the ingress traffic (client to server direction) as traffic will continue to go via the original DC; solutions to solve this challenge include DNS Based, Route Injection, or LISP.

The VLAN ACL is required to identify the traffic that needs to be filtered. This configuration applies to the HSRP v1 & v2 (bold) protocols. After applying the

Even though HSRP traffic is filtered via the VACL, the vMAC used to source the HSRP packets is still learned by the OTV VDC. Therefore, OTV advertises this MAC address information to the other sites via an IS-IS update. While this in itself is not causing harm, it would cause the remote OTV the edge devices to see constant MAC moves happening for the vMAC (from the internal interface to the overlay interface and vice versa).

IP ACL's to drop HSRP Hellos and forward other traffic MAC ACL's to drop non-IP HSRP traffic and forward other traffic Create the VACL & apply the VACL to each extended vlan Feature dhcp required for ARP inspection & create the ARP access-list to deny

traffic from the Virtual MAC & apply ARP ACL to each extended VLAN mac-list to deny advertising virtual MAC, create the route-map, and apply the

route-map to each overlay

configuration on the OTV VDC to the set of VLANs that are trunked from the Agg VDC to the OTV VDC, all HSRP messages will be dropped once received by the OTV VDC. It is also required to apply a specific filter to ensure suppression of the Gratuitous ARP (GARP) messages that may be received across the OTV Overlay from the remote sites.


feature otv

vlan 10, 99

key chain OTV-Key key 1 key-string 0 Cisc0!


interface Overlay 1 otv join-interface ethernet 1/9 otv control-group 239.1.1.1 otv data-group 232.1.1.0/24 otv extend-vlan 10 otv isis authentication-type md5 otv isis authentication key-chain OTV-Key

otv-isis default vpn Overlay1 authentication-check authentication-type md5 authentication key-chain OTV-Key

Step 1 :: configure OTV key chainStep 2 :: apply md5 authentication to OTV HellosStep 3 :: apply md5 authentication to OTV PDUs

OTV ConfigurationOTV Configuration :: Authentication

OTV supports authentication of Hello messages along with authentication of Protocol Data Units (PDU)’s

feature otv

vlan 10, 99

key chain OTV-Key key 1 key-string 0 Cisc0!


interface Overlay 1 otv join-interface ethernet 1/9 otv control-group 239.1.1.1 otv data-group 232.1.1.0/24 otv extend-vlan 10 otv isis authentication-type md5 otv isis authentication key-chain OTV-Key

otv-isis default vpn Overlay1 authentication-check authentication-type md5 authentication key-chain OTV-Key



feature otvfeature ospffeature pim

vlan 10, 99

router ospf 1

ip pim rp-address [x.x.x.x] group-list 224.0.0.0/4ip pim ssm range 232.0.0.0/8

interface loopback 10 ip address [….]/32 ip router ospf 1 area 0 ip pim sparse-mode


interface Overlay 1 otv join-interface loopback 10 otv control-group 239.1.1.1 otv data-group 232.1.1.0/24 otv extend-vlan 10

interface e 1/9 mtu 9216 ip address [….] / 30 ip router ospf 1 area 0.0.0.0 ip ospf network point-to-point ip pim sparse-mode

interface e 2/9 mtu 9216 ip address [….] / 30 ip router ospf 1 area 0.0.0.0 ip ospf network point-to-point ip pim sparse-mode

Step 1 :: enable PIMStep 1 :: configure loopback interface Step 4 :: configure Rendezvous Point (RP) Step 5 :: configure Source-Specific Multicast (SSM)Step 2 :: set OTV joint interface as loopbackStep 3 :: enable PIM sparse on loopbackStep 4 :: enable PIM sparse on all L3 links

OTV ConfigurationOTV Configuration :: Logical Join Interface

Existing Join Interface limitations: Bandwidth to the core / aggregation is limited to

one physical link or port-channel Changes to join-interface will churn all OTV

overlay states, since the overlay encapsulation for all routes need to be updated

PIM cannot be enabled on the join-interface, since the OTV solution assumes it's an IGMP host interface

Unable to utilize the redundancy of multiple uplinks when available, and the flexibility of dynamic unicast routing convergence on uplink failures

If join-interface goes down, the connectivity to the core is broken. User intervention is needed to provide alternate core connectivity


Overlay can now use otv source-interface command to source OTV traffic from the edge device and source joins to receive multicast traffic from the core. Loopback to guarantee interface is up/up.

Multiple L3 uplinks can now connect to OTV edge device, each running PIM and an IGP with IPv4 Core. The OTV edge device can now act as first-hop/last-hop multicast PIM router instead of IGMP client; “ip pim sparse-mode” on all L3 interfaces.


Old Configuration(OTV Join Interface)

Note: OTV Tunnel depolarization will be introduced in a future release. The use of a secondary IP address on the interface, not the OTV interface, will help improve load balancing ECMP for OTV traffic to the core.


feature otv

vlan 10, 99, 100


interface Overlay 1 otv join-interface ethernet 1/9 otv control-group 239.1.1.1 otv data-group 232.1.1.0/24 otv extend-vlan 10 otv vlan mapping 10 to 100

Step 1 :: configure vlan mapping

OTV ConfigurationOTV VLAN Translation :: Translation Through Transit VLAN

When a different VLAN is used at multiple sites A mapped VLAN can not be extended on another site VLAN mappings have a one-to-one relationship VLAN mappings can be added or removed without

impacting all mappings on the overlay interface

feature otv

vlan 20, 99, 100


interface Overlay 1 otv join-interface ethernet 1/9 otv control-group 239.1.1.1 otv data-group 232.1.1.0/24 otv extend-vlan 20 otv vlan mapping 20 to 100

VLAN 10

VLAN 20VLAN 100


feature otv

vlan 10, 99

interface loopback 10 ip address [….]/32


interface Overlay 1 otv join-interface loopback 10 otv control-group 239.1.1.1 otv data-group 232.1.1.0/24 otv broadcast-group 224.2.2.0 otv extend-vlan 10 otv vlan mapping 10

Step 1 :: configure broadcast group

OTV ConfigurationOTV Configuration :: Dedicated Broadcast Group

“otv broadcast-group” configuration line under overlay Optional command Useful for QoS purposes The broadcast group needs to be configured for all OTV

Edge Devices connected to the OTV Overlay network

feature otv

vlan 10, 99

interface loopback 10 ip address [….]/32


interface Overlay 1 otv join-interface loopback 10 otv control-group 239.1.1.1 otv data-group 232.1.1.0/24 otv broadcast-group 224.2.2.0 otv extend-vlan 10 otv vlan mapping 10



feature otv

vlan 10, 99


otv flood mac 1111.2222.0101 vlan 10


Step 1 :: configure static OTV flood [enabled per mac address]

OTV ConfigurationOTV Configuration :: Selective Unicast Flooding

Normally, unknown unicast Layer 2 frames are not flooded between OTV sites, and MAC addresses are not learned across the overlay interface. Any unknown unicast messages that reach the OTV edge device are blocked from crossing the logical overlay, allowing OTV to prevent Layer 2 faults from spreading to remote sites.

The end points connected to the network are assumed to not be silent or unidirectional. However, some data center applications require the unknown unicast traffic to be flooded over the overlay to all the data centers, where end points may be silent. Beginning with Cisco NX-OS Release 6.2(2), you can configure selective unicast flooding to flood the specified destination MAC address to all other edge devices in the OTV overlay network with that unknown unicast traffic.

UnknownUnicast

feature otv

vlan 10, 99



MAC 1 MAC 2


OTV encapsulation is done on M-series modules

Note: The control-plane protocol used by OTV is IS-IS. However, IS-IS does not need to be explicitly configured. It runs in the background once OTV is enabled.

In a multi-tenancy environment, the same OTV VDC can be configured with multiple overlays to provide a segmented Layer 2 extension for different tenants or applications.

When multiple data center sites are interconnected, the OTV operations can benefit from the presence of multicast in the core. Multicast is not mandatory in most OTV topologies (number of sites) since you can use the unicast-mode as well.

The same OTV VDCs can be used by multiple VDCs deployed at the aggregation tier, as well as by other Layer 2 switches connected to the OTV VDCs. This is done by configuring multiple OTV overlays. It's important to note that the extended VLANs within these multiple overlays should not overlap.

A separate Layer 3 link between the two aggregation VDCs should be configured as per best practices to carry any Layer 3 traffic between the them.

The overlay interface will not come up until you configure a multicast group address and the site-VLAN has at least an active port on the OTV edge device.

Support for loopback interfaces as OTV Join interfaces is planned for 6.2(2) and later code releases.

OTV ConfigurationStrong Recommendations and Key Notes


FHRP Filtering Note: It is important to stress how this outbound path (server to client) optimization functionality should be deployed in conjunction with an equivalent one optimizing inbound traffic (client to server) flows to avoid asymmetric traffic behavior (this would be highly undesirable especially in deployments leveraging stateful services across data centers).White Paper discussing inbound traffic optimization solutions :: http://www.cisco.com/en/US/docs/solutions/Enterprise/Data_Center/DCI/4.0/EMC/EMC.pdf

It is important to note how OTV support requires the use of the new Transport Services (TRS) license. Depending on the specifics of the OTV deployment, the Advanced License may be required as well to provide Virtual Device Contexts (VDCs) support.

Before configuring OTV you should review and implement Cisco recommended STP best practices at each site. OTV is independent from STP but it greatly benefits from a stable and robust Layer 2 topology.

If the data centers are OTV multi-homed, it is a recommended best practice to bring the Overlay up in single-homed configuration first, by enabling OTV on a single edge device at each site. After the OTV connection has been tested in as single-homed, then enable the functionality on the other edge devices of each site.

OTV currently enforces switch-virtual-interface (SVI) separation for the VLANs being extended across the OTV link, meaning that OTV is usually in its own VDC. With the VDC license on the Cisco Nexus 7000 you have the flexibility to have SVIs in other VDCs and have a dedicated VDC for OTV functions.

Configure the join interface and all Layer 3 interfaces that face the IP core between the OTV edge devices with the highest maximum transmission unit (MTU) size supported by the IP core. OTV sets the Don't Fragment (DF) bit in the IP header for all OTV control and data packets so the core cannot fragment these packets.


http://www.cisco.com/en/US/docs/solutions/Enterprise/Data_Center/DCI/4.0/EMC/EMC.pdf

http://www.cisco.com/en/US/docs/solutions/Enterprise/Data_Center/DCI/4.0/EMC/EMC.pdf


With NX-OS 6.1 and earlier: Only one join interface can be specified per overlay; two methods are availableConfigure a single join-interface, which is shared across multiple overlaysConfigure a different join interface for each overlay, which increases the OTV reliability

For a higher resiliency, you can use a port-channel, but it is not mandatory. There are no requirements for 1 Gigabit-Ethernet versus 10 Gigabit-Ethernet or dedicated versus shared mode.

The transport network must support PIM sparse mode (ASM) or PIM-Bidir multicast traffic.

OTV is compatible with a transport network configured only for IPv4. IPv6 is not supported.

Do not enable PIM on the join-interface.

Do not configure OTV on an F-series module.

Ensure the site identifier is configured and is the same for all edge devices on a site. OTV brings down all overlays when a mismatched site identifier is detected from a neighbor edge device and generates a system message.

Mixing the Nexus 7000 and the ASR 1000 devices for OTV is not supported at this time when the devices will be placed within the same site. However, using Cisco Nexus 7000s in one site and Cisco ASR 1000s at another site for OTV is fully supported. For this scenario, please keep the separate scalability numbers in mind for the two different devices, because you will have to account for the lowest common denominator.

Starting in NX-OS 5.2, the site-id command was introduced as a way to harden multihoming for OTV. It is a configurable option that must be the same for devices within the same data center and different between any devices that are in different data centers. It specifies which site a particular OTV device is in so that two OTV devices in different sites cannot join each other as a multihomed site. This command is now mandatory.



Using Virtual Port Channels (vPCs) and OTV together provides an extra layer of resiliency and is thus recommended as a best practice.

OTV & FabricPath: Because OTV encapsulation is done on M-series modules, OTV cannot read FabricPath packets. Because of this restriction, terminating FabricPath and reverting to Classical Ethernet where the OTV VDC resides is necessary. In addition, when running FabricPath in your network, we highly recommend that you use the spanning-tree domain <id> command on all devices that are participating in these VLANs. This command speeds up convergence times greatly.



• 42 Bytes overhead to the packet IP MTU size

(Outer IP Header + OTV Shim) – (Original L2 Header without the 802.1Q header)• 802.1Q header is removed and the VLAN field copied over to the OTV shim header• Outer OTV shim header contains VLAN, overlay ID number, and an external IP header• Consider Jumbo MTU Sizing along the path between the source and destination endpoints to account for the extra 42

bytes

OTV ConfigurationOTV Encapsulation :: MAC in IP

20B + 8B + 14B* = 42 Bytes of total overhead

6B 6B 2B 20B 8B

DMAC SMACEtherType IP Header

Payload 4B

CRCOTV Shim

802.1QDMAC SMAC Ether

Type

802.1Q

VLAN ID, Overlay #

14B*

Original L2 Frame

L2 Header

802.1Q header removed

* The 4 Bytes of the 802.1Q header have already been removed

VLA

N


OTV ConfigurationHow OTV Works :: Inter-Site Packet Flow (OTV Data Plane)

MAC TableVLAN MAC IF

10 MAC 1 Eth 1

10 MAC 2 IP B

10 MAC 3 Eth 3

Assumption :: New MACs where learned in the VLANs that are OTV extended on the internal interfaces; an OTV update message was sent and replicated across the transport and delivered to all remote OTV Edge devices; those MACs learned through OTV are then imported in the MAC address tables of the OTV Edge Devices. Step 1 :: The Layer 2 frame is received at the aggregation layer or OTV Edge Device. A traditional Layer 2 lookup is performed, the MAC for Host B’s information in the MAC table does not point to a local Ethernet interface (as you would see in intra-site communication); but to the IP address of the remote OTV Edge Device that advertised that MAC’s reachability information. Step 2 :: The OTV Edge Device encapsulates the original Layer 2 Frame; with is the source IP of the outer header of the local Join interface & the destination IP which is the IP address of the remote Edge Device Join interface.Step 3 :: The OTV encapsulated frame (a regular unicast IP packet) is carried across the transport infrastructure and delivered to the remote OTV Edge Device. Step 4 :: The remote OTV Edge Device decapsulates the frame exposing the original Layer 2 packet. Step 5 :: The OTV Edge Device performs another Layer 2 lookup on the original Ethernet frame and discovers that it is reachable through a physical interface, which means it is a MAC address local to the site. Step 6 :: The frame is then delivered to the MAC destination of Host B

MAC 1 MAC 2

IP A IP BMAC 1 MAC 2

MAC TableVLAN MAC IF

10 MAC 1 IP A

10 MAC 2 Eth 2

10 MAC 3 IP AWEST DC EAST DC

IP A IP BMAC 1 MAC 2

MAC 1 MAC 2

Layer 2 Lookup

Layer 2 Lookup

Encap Decap


External (public)OTV Best Practices Guidehttp://www.cisco.com/en/US/prod/collateral/switches/ps9441/ps9402/guide_c07-728315.pdf

OTV Technology Introduction and Deployment Considerationshttp://www.cisco.com/en/US/docs/solutions/Enterprise/Data_Center/DCI/whitepaper/DCI_1.html

Using OTV to Extend Layer 2 between Two Data Centershttp://www.cisco.com/en/US/prod/collateral/switches/ps9441/ps9402/white_paper_c11-644634.html

Nexus 7000 NX-OS OTV Configuration Guideshttp://www.cisco.com/en/US/docs/switches/datacenter/sw/nx-os/OTV/config_guide/b_Cisco_Nexus_7000_Series_NX-OS_OTV_Configuration_Guide.html

Cisco Nexus 7000 NX-OS Verified Scalability Guide (OTV Limits) http://www.cisco.com/en/US/docs/switches/datacenter/sw/verified_scalability/b_Cisco_Nexus_7000_Series_NX-OS_Verified_Scalability_Guide.html#reference_18192F87114B45D9A40A41A0DEF3F74D

Cisco Live 365 (sign up & search session catalog for OTV)https://ciscolive365.com/ BRKDCT – 3103 :: Advance OTV – Configure, Verify and Troubleshoot OTV in Your Network; Andy Gossett (CSE)

OTV ConfigurationAdditional Resources & Further Reading

Great External Resources

http://www.cisco.com/en/US/prod/collateral/switches/ps9441/ps9402/guide_c07-728315.pdf

http://www.cisco.com/en/US/prod/collateral/switches/ps9441/ps9402/guide_c07-728315.pdf

http://www.cisco.com/en/US/docs/solutions/Enterprise/Data_Center/DCI/whitepaper/DCI_1.html

http://www.cisco.com/en/US/docs/solutions/Enterprise/Data_Center/DCI/whitepaper/DCI_1.html

http://www.cisco.com/en/US/prod/collateral/switches/ps9441/ps9402/white_paper_c11-644634.html

http://www.cisco.com/en/US/prod/collateral/switches/ps9441/ps9402/white_paper_c11-644634.html

http://www.cisco.com/en/US/docs/switches/datacenter/sw/nx-os/OTV/config_guide/b_Cisco_Nexus_7000_Series_NX-OS_OTV_Configuration_Guide.html



http://www.cisco.com/en/US/docs/switches/datacenter/sw/verified_scalability/b_Cisco_Nexus_7000_Series_NX-OS_Verified_Scalability_Guide.html#reference_18192F87114B45D9A40A41A0DEF3F74D



https://ciscolive365.com/

https://ciscolive365.com/


Quick Start Guide :: Virtual Port Channel (vPC)https://communities.cisco.com/docs/DOC-35728

Quick Start Guide :: FabricPathhttps://communities.cisco.com/docs/DOC-35725l

OTV ConfigurationAdditional Resources & Further Reading

https://communities.cisco.com/docs/DOC-35728



http://www.cisco.com/en/US/partner/docs/solutions/Enterprise/Data_Center/VMDC/3.0.1/IG/VMDC301_IG1.html


Documents

Quick Start Guide Overlay Transport Virtualization (OTV)