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Cisco MDS 9000 Family NX-OS Interfaces Configuration Guide
OL-29284-01, Release 6.x
Chapter 7 Configuring N Port Virtualization
Information About N Port Virtualization
NPV CFS Distribution over IP
NPV devices use only IP as the transport medium. CFS uses multicast forwarding for CFS distribution.
NPV devices do not have ISL connectivity and FC domain. To use CFS over IP, multicast forwarding has
to be enabled on the Ethernet IP switches all along the network that physically connects the NPV switch.
You can also manually configure the static IP peers for CFS distribution over IP on NPV-enabled
switches. For more information, see the Cisco MDS 9000 Family NX-OS System Management
Configuration Guide.
NPV Traffic Management
This sections discusses the following aspects of load balancing:
Auto, page 7-7
Traffic Map, page 7-7
Disruptive, page 7-8

Auto

Before Cisco MDS SAN-OS Release 3.3(1a), NPV supported automatic selection of external links.
When a server interface is brought up, an external interface with the minimum load is selected from the
available links. There is no manual selection on the server interfaces using the external links. Also, when
a new external interface was brought up, the existing load was not distributed automatically to the newly
available external interface. This newly brought up interface is used only by the server interfaces that
come up after this interface.

Traffic Map

As in Cisco MDS SAN-OS Release 3.3(1a) and NX-OS Release 4.1(1a), NPV supports traffic
management by allowing you to select and configure the external interfaces that the server uses to
connect to the core switches.
Note When the NPV traffic management is configured, the server uses only the configured external interfaces.
Any other available external interface will not be used.
The NPV traffic management feature provides the following benefits:
Facilitates traffic engineering by providing dedicated external interfaces for the servers connected
to NPV.
Uses the shortest path by selecting external interfaces per server interface.
Uses the persistent FC ID feature by providing the same traffic path after a link break, or reboot of
the NPV or core switch.
Balances the load by allowing the user to evenly distribute the load across external interfaces.