
Route Leaking VRFs
Static routes can be used to redistribute routes between non-default to default/non-default VRF and vice-versa.
You can configure route leaking between two VRFs using the following command:
ip route vrf x.x.x.x s.s.s.s
nh.nh.nh.nh vrf default.
This command indicates that packets that are destined to
x.x.x.x/s.s.s.s
are reachable through
nh.nh.nh.nh
in the default
VRF table. Meaning, the routes to
x.x.x.x/s.s.s.s
are leaked from the default VRF routing table into the non-default VRF
routing table.
The following example illustrates how route leaking between two VRFs can be performed:
interface TenGigabitEthernet 1/9
ip vrf forwarding VRF1
ip address 120.0.0.1/24
interface TenGigabitEthernet 1/10
ip vrf forwarding VRF2
ip address 140.0.0.1/24
ip route vrf VRF1 20.0.0.0/16 140.0.0.2 vrf VRF2
ip route vrf VRF2 40.0.0.0/16 120.0.0.2 vrf VRF1
Dynamic Route Leaking
Route Leaking is a powerful feature that enables communication between isolated (virtual) routing domains by segregating and
sharing a set of services such as VOIP, Video, and so on that are available on one routing domain with other virtual domains. Inter-
VRF Route Leaking enables a VRF to leak or export routes that are present in its RTM to one or more VRFs.
Dynamic Route Leaking enables a source VRF to share both its connected routes as well as dynamically learnt routes from various
protocols, such as ISIS, OSPF, BGP, and so on, with other default or non-default VRFs.
You can also leak global routes to be made available to VRFs. As the global RTM usually contains a large pool of routes, when the
destination VRF imports global routes, these routes will be duplicated into the VRF's RTM. As a result, it is mandatory to use route-
maps to filter out leaked routes while sharing global routes with VRFs.
Configuring Route Leaking without Filtering Criteria
You can use the
ip route-export tag
command to export all the IPv4 routes corresponding to a source VRF. For leaking IPv6
routes, use the
ipv6 route-export tag
command. This action exposes source VRF's routes (IPv4 or IPv6 depending on the
command that you use) to various other VRFs. The destinations or target VRFs then import these IPv4 or IPv6 routes using the
ip
route-import tag
or the
ipv6 route-import tag
command respectively.
NOTE: In Dell Networking OS, you can configure at most one route-export per VRF as only one set of routes can be
exposed for leaking. However, you can configure multiple route-import targets because a VRF can accept routes from
multiple VRFs.
After the target VRF learns routes that are leaked by the source VRF, the source VRF in turn can leak the export target
corresponding to the destination VRFs that have imported its routes. The source VRF learns the export target corresponding to the
destinations VRF using the
ip route-import tag
or
ipv6 route-import tag
command. This mechanism enables reverse
communication between destination VRF and the source VRF.
If the target VRF contains the same prefix (either sourced or Leaked route from some other VRF), then the Leak for that particular
prefix will fail and an error-log will be thrown. Manual intervention is required to clear the unneeded prefixes. The source route will
take priority over the leaked route and the leaked route is deleted.
Consider a scenario where you have created four VRF tables VRF-red, VRF-blue, VRF-Green, and VRF-shared. The VRF-shared
table belongs to a particular service that should be made available only to VRF-Red and VRF-Blue but not VRF-Green. For this
972
Virtual Routing and Forwarding (VRF)
Содержание S4048-ON
Страница 1: ...Dell Configuration Guide for the S4048 ON System 9 9 0 0 ...
Страница 146: ...Figure 14 BFD Three Way Handshake State Changes 146 Bidirectional Forwarding Detection BFD ...
Страница 477: ...Figure 68 Inspecting Configuration of LAG 10 on ALPHA Link Aggregation Control Protocol LACP 477 ...
Страница 480: ...Figure 70 Inspecting a LAG Port on BRAVO Using the show interface Command 480 Link Aggregation Control Protocol LACP ...
Страница 481: ...Figure 71 Inspecting LAG 10 Using the show interfaces port channel Command Link Aggregation Control Protocol LACP 481 ...
Страница 522: ...Figure 87 Configuring Interfaces for MSDP 522 Multicast Source Discovery Protocol MSDP ...
Страница 523: ...Figure 88 Configuring OSPF and BGP for MSDP Multicast Source Discovery Protocol MSDP 523 ...
Страница 524: ...Figure 89 Configuring PIM in Multiple Routing Domains 524 Multicast Source Discovery Protocol MSDP ...
Страница 528: ...Figure 91 MSDP Default Peer Scenario 1 528 Multicast Source Discovery Protocol MSDP ...
Страница 529: ...Figure 92 MSDP Default Peer Scenario 2 Multicast Source Discovery Protocol MSDP 529 ...
Страница 530: ...Figure 93 MSDP Default Peer Scenario 3 530 Multicast Source Discovery Protocol MSDP ...
Страница 633: ...Policy based Routing PBR 633 ...
Страница 777: ...Figure 119 Single and Double Tag TPID Match Service Provider Bridging 777 ...
Страница 778: ...Figure 120 Single and Double Tag First byte TPID Match 778 Service Provider Bridging ...