H3C Technologies H3C S12500 Series Switches - Manual (Page 419)

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Configuring routing policies
Routing policy in this chapter involves both IPv4 routing policy and IPv6 routing policy.
Introduction to routing policy
A routing policy is used to filter routes when they are received, advertised, or redistributed and modify
the attributes of some routes.
Routing policy application
A routing policy has the following applications:
• Filter advertised routes.
• Filter received routes.
• Filter redistributed routes.
• Modify or set the attributes of some routes.
Routing policy implementation
To configure a routing policy, you must do the following:
1. Define some filters based on the attributes of routing information, such as destination address, and
the advertising router's address.
2. Then apply the filters to the routing policy.
You can use multiple filters flexibly to define match criteria. For detailed information, see " Filters ."
Filters
There are several types of filters: ACL, IP prefix list, AS path list, community list, extended community list,
and routing policy.
ACL
ACL involves IPv4 ACL and IPv6 ACL. An ACL is configured to match the destinations or next hops of
routing information.
For more information about ACL, see ACL and QoS Configuration Guide.
IP prefix list
IP prefix list involves IPv4 prefix list and IPv6 prefix list.
An IP prefix list is configured to match the destination address of routing information. Moreover, you can
use the gateway option to allow only routing information from certain routers to be received. For
gateway option information, see Layer 3—IP Routing Command Reference.