Huawei Quidway S5600 Series Operation Manual page 392

Operation Manual – Routing Protocol
Quidway S5600 Series Ethernet Switches-Release 1510
Normally, a basic ACL is used to filter routing information. You can specify a range of IP
addresses or subnets when defining a basic ACL so as to match the destination
network segment addresses or next-hop addresses of routing information. If an
advanced ACL is used, the specified range of source addresses will be used for
matching.
For ACL configuration, see the QoS/ACL configuration section of this manual.
III. ip-prefix
ip-prefix plays a role similar to ACL. But it is more flexible than ACL and easier to
understand. When ip-prefix is applied to filtering routing information, its matching object
is the destination address information field of routing information. Moreover, with
ip-prefix, you can use the gateway option to specify that only routing information
advertised by certain routers will be received.
An ip-prefix is identified by its ip-prefix name. Each ip-prefix can include multiple items,
and each item, identified by an index-number, can independently specify the match
range in network prefix form. An index-number specifies the matching sequence in the
ip-prefix.
During the matching, the router checks items identified by index-number in ascending
order. Once an item is met, the ip-prefix filtering is passed and no other item will be
checked.
IV. as-path
as-path is an access control list of autonomous system path. It is only used in BGP to
define the matching conditions about AS path. An as-path contains a series of AS paths
which are the records of routing information passed paths during BGP routing
information exchange. .
V. community-list
community-list is only used to define the matching conditions about community
attributes in BGP. A BGP routing information packet contains a community attribute field
used to identify a community.
Huawei Technologies Proprietary
6-2
Chapter 6 IP Routing Policy Configuration