N Port Virtualization - Cisco MDS 9000 Series Configuration Manual

Configuring N Port Virtualization

N Port Virtualization

Note All of the N port identifiers are allocated in the same VSAN.
N Port Virtualization
Typically, Fibre Channel networks are deployed using a core-edge model with a large number of fabric
switches connected to edge devices. Such a model is cost-effective because the per port cost for director class
switches is much higher than that of fabric switches. However, as the number of ports in the fabric increases,
the number of switches deployed also increases, and you can end up with a significant increase in the number
of domain IDs. This challenge becomes even more difficult when additional blade chassis are deployed in
Fibre Channel networks.
NPV addresses the increase in the number of domain IDs needed to deploy a large number of the ports by
making a fabric or blade switch appear as a host to the core Fibre Channel switch, and as a Fibre Channel
switch to the servers in the fabric or blade switch. NPV aggregates multiple locally connected N ports into
one or more external NP links, which shares the domain ID of the NPV core switch among multiple NPV
switches. NPV also allows multiple devices to attach to same port on the NPV core switch, which reduces
the need for more ports on the core
For more information on scalability limits, see the Cisco MDS NX-OS Configuration Limits guide.
Figure 19: Cisco NPV Fabric Configuration
While NPV is similar to N port identifier virtualization (NPIV), it does not offer exactly the same functionality.
NPIV provides a means to assign multiple FC IDs to a single N port, and allows multiple applications on the
N port to use different identifiers. NPIV also allows access control, zoning, and port security to be implemented
at the application level. NPV makes use of NPIV to get multiple FCIDs allocated from the core switch on the
NP port.
Figure 20: Cisco NPV Configuration-Interface View, on page 253 shows a more granular view of an NPV
configuration at the interface level.
Cisco MDS 9000 Series Interfaces Configuration Guide, Release 8.x
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