reflect change-path-attribute

However, if you need to re-plan the network traffic, you can run the reflect change-path-attribute command to enable the RR to modify the route attributes based on the export policy. After the reflect change-path-attribute command is enabled on an RR, you can perform the following operations as required:

• Run the apply as-path command to modify the AS-Path attributes of BGP routes.
• Run the apply comm-filter delete command to delete all community attributes from BGP routes.
• Run the apply community command to modify the community attributes of BGP routes.
• Run the apply cost command to modify the cost of BGP routes, that is to modify its Multi_Exit Discriminator (MED) value.
• Run the apply ip-address nexthop command to modify the next hop of BGP routes.
• Run the apply ipv6 next-hop command to modify the next hops of BGP4+ routes.
• Run the apply local-preference command to modify the local preferences of BGP routes.
• Run the apply origin command to modify the Origin attributes of BGP routes.
• Run the apply extcommunity command to modify the extended community attributes of BGP routes.

For example, a peer relationship is established between Router A (1.1.1.1) and Router B (2.2.2.2), and Router A functions as an RR. If the following export policy is configured on RouterA:

[sysname] route-policy aa permit node 10

[sysname-route-policy] apply ip-address next-hop 1.1.1.1

[sysname-route-policy] quit

[sysname] bgp 65001

[sysname-bgp] peer 2.2.2.2 route-policy aa export

Then:

• If the reflect change-path-attribute command is not run, Router A reflects routes advertised by other IBGP peers to Router B without changing the next hops of these routes.

• If the reflect change-path-attribute command is run, Router A changes the next hops of the routes advertised by other IBGP peers to 1.1.1.1 before reflecting these routes to Router B.