Virtualization Support; Licensing Requirements For The Unicast Rib And Fib; Guidelines And Limitations - Cisco Nexus 7000 Series Configuration Manual

Chapter 15 Managing the Unicast RIB and FIB
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 .
Table 15-1
Region
IPv4 multicast routes
or
IPv6 unicast routes
IPv6 multicast routes
Full IPv4 Internet route tables have more than 256K routes, which is more than the maximum number
Note
of Cisco NX-OS FIB entries.
Dynamic TCAM allocation can reallocate unused TCAM blocks to an adjacent region when all existing
blocks in that region are full. Dynamic TCAM allocation allows more flexibility in the number of routes
that the FIB can allocate for a route type.
You may need to disable dynamic TCAM allocation if you downgrade to a release earlier than Cisco
Note
NX-OS Release 4.2(1).

Virtualization Support

The Unicast RIB and FIB support Virtual Routing and Forwarding instances (VRFs). VRFs exist within
virtual device contexts (VDCs). By default, Cisco NX-OS places you in the default VDC and default
VRF unless you specifically configure another VDC and VRF. For more information, see the Cisco Cisco
Nexus 7000 Series NX-OS Virtual Device Context Configuration Guide, Release 4.x and see
"Configuring Layer 3 Virtualization."

Licensing Requirements for the Unicast RIB and FIB

The following table shows the licensing requirements for this feature:
Product License Requirement
Cisco NX-OS The unicast RIB and FIB require no license. Any feature not included in a license package is bundled with
the Cisco NX-OS system images and is provided at no extra charge to you. For a complete explanation of
the NX-OS licensing scheme, see the Cisco NX-OS Licensing Guide.

Guidelines and Limitations

Unicast RIB and FIB have the following guidelines and limitations and restrictions:
•
OL-20002-02
Default FIB TCAM Allocation (continued)
Default Number of Routes Number of TCAM blocks
32K
2K
The FIB TCAM has 128K physical entries, which is divided into the following sections by default:
– 56K IPv4 unicast routes (56K physical entries)
32K IPv4 multicast routes or IPv6 unicast routes (64K physical entries)
–
2K IPv6 multicast routes (8K physical entries)
–
Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x
Licensing Requirements for the Unicast RIB and FIB
8
1
Entry size
144 bits
288 bits
Chapter 14,
15-3