Configuring bgp route attributes, Configuration prerequisites, Specifying a preferred value for routes received – H3C Technologies H3C SecPath F1000-E User Manual

Page 482: Configuring preferences for bgp routes, Configuring the default local preference

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Step Command

Remarks

3.

Configure a shortcut route.

network ip-address [ mask |
mask-length ] short-cut

Optional.
By default, an EBGP route

received has a priority of 255.

Configuring BGP route attributes

Configuration prerequisites

Create BGP connections.

Specifying a preferred value for routes received

By default, routes received from a peer have a preferred value of 0. Among multiple routes that have the
same destination/mask and are learned from different peers, the one with the greatest preferred value

is selected as the route to the destination.
To specify a preferred value for routes from a peer or peer group:

Step Command

Remarks

1.

Enter system view.

system-view

N/A

2.

Enter BGP view.

bgp as-number

N/A

3.

Specify a preferred value for
routes received from a peer or

peer group.

peer { group-name | ip-address }
preferred-value value

Optional
By default, the preferred value
is 0.

Configuring preferences for BGP routes

A router may run multiple routing protocols with each having a preference. If they find the same route, the

route found by the routing protocol with the highest preference is selected.
This task allows you to configure preferences for external, internal, and local BGP routes, and reference

a routing policy to set preferences for matching routes as needed.
To configure preferences for BGP routes:

Step Command

Remarks

1.

Enter system view.

system-view

N/A

2.

Enter BGP view.

bgp as-number

N/A

3.

Configure preferences for
external, internal, local BGP

routes.

preference { external-preference
internal-preference local-preference
| route-policy route-policy-name }

Optional.
The default preferences of
external, internal, and local

BGP routes are 255, 255, and

130, respectively.

Configuring the default local preference

The local preference is used to determine the best route for traffic leaving the local AS. When a BGP

router obtains from several IBGP peers multiple routes to the same destination but with different next hops,

it considers the route with the highest local preference as the best route.

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