Cisco ASR 9000 Series Routing Configuration Guide

Selective VRF Download Disable
Selective VRF Download (SVD) functionality is disabled, by default. To enable SVD, configure the svd
platform enable command in administrative configuration mode and reload the chassis using the reload
location all command. To disable SVD that is already enabled, use the no svd platform enable command
and reload the chassis using the reload location all command.
Calculating Routes Downloaded to Line Card with or without SVD
The number of routes that will be downloaded to the line card with or without selective VRF download option
can be calculated by following the Total Tables and Routes Downloaded by Line Card Type table below.
This table summarizes the total routes and tables downloaded on the line cards of each SVD card type. Savings
can be calculated by the difference between the numbers in the Without SVD row.
Table 2: Total Tables and Routes Downloaded by Line Card Type
Routes DownloadedTables DownloadedCard Type
(o+Y)R(o+Y)Customer
nxRnCore
nRnWithout SVD
•
n is the total number of VRFs present
•
o is the number of VRF directly provisioned/configured on the card, (n is greater than or equal to o)
•
R is routes per VRF
•
x is the ratio of SVD local: total routes
•
Y is the number of VRFs dependant on directly provisioned VRFs (o), (Y is greater than or equal to 0)
Here is an example calculation:
A customer has 100 VRFs configured on the system, with five line cards. For the IPv4 address family, four
line cards are working as customer facing with equal VRF distribution, while one is core facing. Inter-table
dependencies do not exist. In this example, n = 100, o = 25, x = 3/10, Y = 0, and R = 1000.
Number of routes downloaded:
•
Without SVD: (nR) = 100,000
•
On customer-facing card: (o+Y)R = 25,000
•
On core-facing card: (nxR) = 30,000
In this example, the SVD feature brings close to 70 per cent savings.
The total number of VRFs present (n) can be found by using the show cef tables summary location node-id
command on the RSP card.
RP/0/RSP0/CPU0:router#show cef tables summary location 0/rsp0/cpu0
Cisco ASR 9000 Series Aggregation Services Router Routing Configuration Guide, Release 5.3.x
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Implementing BGP
Selective VRF Download Disable

Cisco ASR 9000 Series Specifications

General

Series	ASR 9000
Category	Network Router
Modular Design	Yes
Redundancy	Yes (Hardware and Software)
Operating System	Cisco IOS XR
Interfaces/Ports	10G, 40G, 100G, 400G Ethernet
Expansion Slots	Varies by model
Routing Protocol	BGP, OSPF, IS-IS, EIGRP
Management	CLI, SNMP, NETCONF
Power Supply	Redundant
Port Density	Varies by model
Power Supply Options	AC, DC
Memory	Varies by model
Storage	Varies by model
Dimensions	Varies by model
Weight	Varies by model