OmniSwitch os6900, Руководство по настройке сети

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Configuring IP VRF Route Leak
OmniSwitch AOS Release 7 Network Configuration Guide June 2013 page 15-37
VRF Route Leak
VRF provides isolation of routing instances from each other. The basic principle of VRF is to exclude two
or more routing domains mutually by containing the exchange of routing information and forwarding
packets within the same routing instance. VRF provides independent routing instances logically
separating Layer3 topology of unrelated entities sharing a single physical infrastructure.
However, network devices in one VRF might need to access selected network devices in another VRF,
such as in the following scenarios:
•
In an enterprise, various departments can be isolated in individual VRFs but users in all the VRFs need
access to the Mail Server/common enterprise portal.
•
Users in other VRFs need internet access that is available in only one VRF.
•
Buildings where multiple companies sharing the same router reside in individual VRFs have to access
common services like logistics, common network equipment that is a part of an independent VRF.
VRF Route Leak feature can be used to forward routes from one VRF routing table to another VRF
routing table, allowing routing from one VRF to a gateway in another VRF.
Quick Steps for Configuring VRF Route Leak
The following steps provide a quick tutorial on how to configure VRF Route Leak. Each step describes a
specific operation and provides the CLI command syntax for performing that operation.
1
Create a route-map to use as a filter for exporting or importing routes.
-> ip route-map R1 action permit
2
Define protocol preference for export policy route map using the ip route-map match command. This
route map controls the export of routes from the VRF FDB (Forwarding Routing Database) to the GRT
(Global Routing Table). A route-map with no specific match clause matches all FDB routes. For example,
-> ip route-map R1 match protocol static
3
Export routes from the source VRF to the GRT using the ip export command.
For example,
-> ip export route-map R1
4
Define protocol preference for import policy route map using the ip route-map match command. This
route map controls the import of routes from the GRT. For example,
-> ip route-map R2 match protocol static
5
Import the leaked routes from the GRT using the ip import command. For example,
-> ip import vrf V1 import route-map R2
6
Configure route preference for imported routes using the ip route-pref command with the import
parameter. For example,
-> ip route-pref import 100
7
Redistribute imported routes to other routing protocols that are imported and added to the RDB from
other VRFs using the ip redist command. For example,