Controlling route distribution and reception, Configuring bgp route summarization, Configuring automatic route summarization – H3C Technologies H3C S12500 Series Switches User Manual

Page 229: Configuring manual route summarization

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213

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.

Enable route redistribution
from IGP into BGP.

import-route protocol [ { process-id
| all-processes } [ allow-direct |
med med-value | route-policy

route-policy-name ] * ]

Not enabled by default.
The allow-direct keyword is
available only when the specified

routing protocol is OSPF.

4.

Enable default route
redistribution into BGP.

default-route imported

Not enabled by default.

Controlling route distribution and reception

Configuring BGP route summarization

To reduce the number of routes to be redistributed and the routing table size on medium and large BGP

networks, configure route summarization on BGP routers. BGP supports the following summarization

modes: automatic and manual. Manual summary routes have a higher priority than automatic ones.

Configuring automatic route summarization

After automatic route summarization is configured, BGP summarizes redistributed IGP subnets to

advertise only natural networks. Routes injected with the network command cannot be summarized.
To configure automatic route summarization:

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.

Configure automatic route
summarization.

summary automatic

Not configured by default.

Configuring manual route summarization

By configuring manual route summarization, you can summarize both redistributed routes and routes

injected using the network command and determine the mask length for a summary route as needed.
To configure BGP manual route summarization:

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