nx.os.and.cisco.nexus.switching.2nd.edition.1587143046

the overlay; this enables data center simplification and Spanning Tree Root Bridge
independence per data center for all virtual local area networks (VLANs) extended across
OTV.
Figure 11-1 shows a common deployment and topology deployed in many Enterprise
accounts. Having an OTV Virtual Device Context (VDC) is a best practice; this is a
mandatory requirement if the VLANs extended via OTV require a Layer 3 Switched Virtual
Interface (SVI) to a given VLAN. The topology in Figure 11-1 is explained and referenced
throughout the rest of the chapter.
OTV Terminology and Concepts
Figure 11-1. OTV Topology
Before understanding and learning the OTV control-plane and data-plane operations, the
OTV terminology needs to be defined and understood:
• OTV Edge Device: The OTV Edge Device performs the OTV function and
operations. The OTV Edge Device receives the Layer 2 Ethernet traffic for all VLANs
that need to be extended between OTV peers and dynamically encapsulates the
Ethernet frames into IP packets that are then sent across the transport infrastructure.
Because the OTV Edge Device needs to see the Layer 2 traffic, it is recommended to
place the Edge Device at the Layer 2 or Layer 3 boundary of the data center
aggregation layer. However, the OTV Edge Device can be positioned in different
places of the data center network and is extremely flexible based on the requirements
and data center topology. It is recommended but not required to deploy the OTV Edge
Device in pairs for redundancy, load balancing, and resiliency. The OTV edge device
is typically carved up into a VDC on each Nexus 7000.