Route reflectors
Router reflectors are another technology designed to help BGP scale to a large AS. In a route reflector configuration there is at least one route reflector server and one or more route reflector clients. In example shown in the following figure, router R1 is the route reflector server and router R2, R3, and R4 are the route reflector clients.
This example assumes that the configurations in previous sections have been performed, and that interfaces and OSPF have been configured. If you are starting from a clean base system, you need not delete previous configuration.
Router | Step | Commands |
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R1 | Delete current BGP configuration. |
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R1 | To allow routes from AS200 to be injected into RIB on R2. |
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R1 | Set R2 in the same AS as R1. |
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R1 | Set R2 as a route reflector client. |
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R1 | Define the IP address on the local R1 router that is used to peer with the R2 router. |
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R1 | To allow routes from AS200 to be injected into RIB on R3. |
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R1 | Set R3 in the same AS as R1. |
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R1 | Set R3 as a route reflector client. |
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R1 | Define the IP address on the local R1 router that is used to peer with the R3 router. |
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R1 | To allow routes from AS200 to be injected into RIB on R4. |
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R1 | Set R4 in the same AS as R1. |
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R1 | Activate the neighbor for the IPv4 unicast address family to enable the exchange IPv4 unicast routes. |
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R1 | Set R4 as a route reflector client. |
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R1 | Define the IP address on the local R1 router that is used to peer with the R4 router. |
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R1 | Set the AS200 router in a different AS than R1. |
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R1 | Set the outbound filter. |
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R1 | Set the inbound filter. |
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R1 | Set the network to advertise. |
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R1 | Set the router ID. |
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R1 | Commit the configuration. |
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R1 | Display the BGP configuration. |
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R2 | Delete current BGP configuration. |
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R2 | Set R1 in the same AS as R2. |
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R2 | Define the IP address on the local R2 router that is used to peer with the R1 router. |
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R2 | Activate the neighbor for the IPv4 unicast address family to enable the exchange IPv4 unicast routes. |
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R2 | Set the network to advertise. |
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R2 | Set the router ID. |
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R2 | Commit the configuration. |
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R2 | Display the BGP configuration. |
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R3 | Delete current BGP configuration. |
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R3 | Set R1 in the same AS as R3. |
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R3 | Define the IP address on the local R3 router that is used to peer with the R1 router. |
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R3 | Activate the neighbor for the IPv4 unicast address family to enable the exchange IPv4 unicast routes. |
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R3 | Set the network to advertise. |
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R3 | Set the router ID. |
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R3 | Commit the configuration. |
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R3 | Display the BGP configuration. |
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R4 | Delete current BGP configuration. |
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R4 | To allow routes from AS300 to be injected into RIB on R1. |
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R4 | Set R1 in the same AS as R4. |
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R4 | Define the IP address on the local R4 router that is used to peer with the R1 router. |
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R4 | Set the AS300 router in a different AS than R4. |
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R4 | Set the outbound filter. |
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R4 | Set the inbound filter. |
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R4 | Activate the neighbor for the IPv4 unicast address family to enable the exchange IPv4 unicast routes. |
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R4 | Set the network to advertise. |
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R4 | Set the router ID. |
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R4 | Commit the configuration. |
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R4 | Display the BGP configuration. |
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