R3303-HP 6600/HSR6600 Routers Layer 3 - IP Routing Configuration Guide

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Configuration prerequisites
Peering nodes are accessible to each other at the network layer.
Configuring BGP community
By default, a router does not send the community or extended community attribute to its peers or peer
groups. When the router receives a route carrying the community or extended community attribute, it
removes the attribute before advertising the route to its peers or peer groups.
This task allows you to enable a router to advertise the community or extended community attribute to its
peers, so that you can implement route filtering and control. By using this configuration together with a
routing policy, you can add and modify the community or extended community attribute of a route. For
more information about routing policy, see "Configuring routing policies."
To configure BGP community:
Step Command Remarks
1. Enter system view.
system-view N/A
2. Enter BGP view or BGP-VPN
instance view.
• Enter BGP view:
bgp as-number
• Enter BGP-VPN instance view:
a. bgp as-number
b. ipv4-family vpn-instance
vpn-instance-name
Use either method.
3. Advertise the community
attribute or extended
community attribute to a peer
or peer group.
• Advertise the community
attribute to a peer or peer
group:
peer { group-name |
ip-address }
advertise-community
• Advertise the extended
community attribute to a peer or
peer group:
peer { group-name |
ip-address }
advertise-ext-community
Use either method.
Not configured by default.
4. Apply a routing policy to
routes advertised to a peer or
peer group.
peer { group-name | ip-address }
route-policy route-policy-name
export
Not configured by default.
Configuring a BGP route reflector
If an AS has many BGP routers, you can configure them as a cluster and configure one of them as a route
reflector and others as clients to reduce IBGP connections.
To enhance network reliability and prevent single point of failure, specify multiple route reflectors for a
cluster. The route reflectors in the cluster must have the same cluster ID to avoid routing loops.