Layer 3 Virtualization - Cisco Nexus 7000 Series Configuration Manual

Layer 3 Virtualization

S e n d d o c u m e n t c o m m e n t s t o n e x u s 7 k - d o c f e e d b a c k @ c i s c o . c o m .
OSPF is an example of a link-state protocol.
Layer 3 Virtualization
Cisco NX-OS introduces the virtual device context (VDC), which provides separate management
domains per VDC and software fault isolation. Each VDC supports multiple Virtual Routing and
Forwarding Instances (VRFs) and multiple routing information bases (RIBs) to support multiple address
domains. Each VRF is associated with a routing information base (RIB) and this information is collected
by the Forwarding Information Base (FIB).
the Cisco NX-OS system.
Figure 1-3 Layer 3 Virtualization Example
Cisco NX-OS System
A VRF represents a layer 3 addressing domain. Each layer 3 interface (logical or physical) belongs to
one VRF. A VRF belongs to one VDC. Each VDC can support multiple VRFs. For more information,
see
See to the Cisco Nexus 7000 Series NX-OS Virtual Device Context Configuration Guide, Release 4.x for
details on VDCs.
Cisco NX-OS Fowarding Architecture
The Cisco NX-OS forwarding architecture is responsible for processing all routing updates and
populating the forwarding information to all modules in the chassis.
This section includes the following topics:
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Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x
1-10
VDC 1
Protocol VRF
Routing
Protocol VRF
RIBs
RIB table RIB table
Chapter 14, "Configuring Layer 3 Virtualization."
Unicast RIB, page 1-11
Adjacency Manager, page 1-11
Unicast Forwarding Distribution Module, page 1-12
FIB, page 1-12
Figure 1-3 shows the relationship between VDC, VRF, and
VDC n
Routing
RIBs
Forwarding Information Bases
VRF n
VRF 1
Routing Protocol
RIB table RIB table
Chapter 1 Overview
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