Defining Secondary Routing Table Lookup - Juniper BGP - CONFIGURATION GUIDE V 11.1.X Configuration Manual

JUNOSe 11.1.x BGP and MPLS Configuration Guide

Defining Secondary Routing Table Lookup

You can enable secondary routing table lookup on the virtual router routing table of
the parent (global) virtual router. The secondary lookup takes place when the initial
route lookup on a VRF is unsuccessful. You can define secondary routing table lookup
outside the context of the VRF or inside the context of the VRF.
To configure secondary routing table lookup from outside the VRF context:
1.
2.
To specify from inside the VRF context that an interface use the fallback global routing
table lookup:
1.
2.
3.
ip fallback global
ip vrf forwarding
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Configuring BGP VPN Services
Use the no version to remove the interface assignment or discontinue secondary
routing table lookup.
See ip vrf forwarding.
Select the interface.
host1:vr1(config)#interface gigabitEthernet 1/0
Specify a VRF and that you want it to perform secondary routing table lookup.
host1:vr1(config-if)#ip vrf forwarding vrfA fallback global
host1:vr1:vrfA(config-if)#ip address 10.12.4.5 255.255.255.0
Select the interface.
host1:vr1(config)#interface gigabitEthernet 1/0
Enter the VRF context.
host1:vr1(config-if)#virtual-router :vrfA
Specify that the VRF perform a secondary routing table lookup.
host1:vr1:vrfA(config-if)#ip fallback global
Use to specify secondary routing table lookup for an interface in a VRF if an
initial routing table lookup is unsuccessful.
Example
host1:vr1:vrfA(config-if)#ip fallback global
Use the no version to discontinue secondary routing table lookup.
See ip fallback global.