Vrf And Routing; Vrf-Aware Services - Cisco Nexus 7000 Series Configuration Manual

Chapter 14 Configuring 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 .

VRF and Routing

All unicast and multicast routing protocols support VRFs. When you configure a routing protocol in a
VRF, you set routing parameters for the VRF that are independent of routing parameters in another VRF
for the same routing protocol instance.
You can assign interfaces and route protocols to a VRF to create virtual Layer 3 networks. An interface
exists in only one VRF.
VRFs. Routers Z, A, and B exist in VRF Red and form one address domain. These routers share route
updates that do not include router C because router C is configured in a different VRF.
Figure 14-2
Router Z
By default, Cisco NX-OS uses the VRF of the incoming interface to select which routing table to use for
a route lookup. You can configure a route policy to modify this behavior and set the VRF that Cisco
NX-OS uses for incoming packets. See
information.
Cisco NX-OS prevents route leakage(import or export) between VRFs.

VRF-Aware Services

A fundamental feature of the Cisco NX-OS architecture is that every IP-based feature is VRF aware.
The following VRF-aware servics can select a particular VRF to reach a remote server or to filter
information based on the selected VRF:
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OL-20002-02
Figure 14-2
VRFs in a Network
Ethernet 1/1
VRF Red
AAA—See the Cisco Nexus 7000 Series NX-OS Security Configuration Guide, Release 4.x for more
information.
Call Home—See the Cisco Nexus 7000 Series NX-OS System Management Configuration Guide,
Release 4.x for more information.
DNS—See Chapter 4, "Configuring DNS"
GLBP—See Chapter 18, "Configuring GLBP"
HSRP—See Chapter 19, "Configuring HSRP"
HTTP—See the Cisco Nexus 7000 Series NX-OS Fundamentals Configuration Guide, Release 4.x
for more information.
Licensing—See theCisco NX-OS Licensing Guide for more information.
NetFlow—See the Cisco Nexus 7000 Series NX-OS System Management Configuration Guide,
Release 4.x for more information.
NTP—See the Cisco Nexus 7000 Series NX-OS System Management Configuration Guide, Release
4.x for more information.
Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x
shows one physical network split into two virtual networks with two
Router A
Ethernet 2/1
VRF Red
Ethernet 2/2
VRF Blue
Chapter 17, "Configuring Policy-Based Routing"
for more information.
for more information.
for more information.
Layer 3 Virtualization
Router B
Router C
for more
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