H3C Technologies H3C S10500 Series Switches - Manual (Page 224)

209
To do… Use the command… Remarks
Enable route redistribution from a
routing protocol into BGP
import-route protocol [ { process-id
| all-processes } [ allow-direct |
med med-value | route-policy
route-policy-name ] * ]
Required
Not redistributed by default
The allow-direct keyword is
available only when the specified
routing protocol is OSPF.
Enable default route redistribution
into BGP
default-route imported
Optional
Not enabled by default
Controlling route distribution and reception
Configuration prerequisites
BGP connections must be created.
Configuring BGP route summarization
To reduce the routing table size on medium and large BGP networks, you need to configure route
summarization on BGP routers. BGP supports automatic and manual summarization modes. Manual
summary routes have a higher priority than automatic ones.
NOTE:
The output interface of BGP summary routes is Null 0. If the network address and mask of a specific route
are the same as the summary route, BGP selects the route with higher preference to guide packet
forwarding.
Configure 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.
Follow these steps to configure automatic route summarization:
To do… Use the command… Remarks
Enter system view system-view —
Enter BGP view bgp as-number —
Configure automatic route
summarization
summary automatic
Required
Not configured by
default.
Configure 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.
Follow these steps to configure BGP manual route summarization: