Route Filtering By Means Of As_Path - Zte ZXR10 GER User Manual

In this example, the route-map command and the access list
command access-list are used to prevent R1 from advertising
prefix 192.18.10.0/24 to AS200.
This command can also be used to filter certain network prefix to
be advertised.
ZXR10(config-router)#bgp filter out deny peer-ip 182.17.20.1
network 192.18.10.0 0.0.0.255
Route Filtering by Means of
AS_PATH
Introduction If all routers in one or multiple ASs need filtering, normally route
filtering based on AS path information is used. This filtering
method can avoid the complexity caused by prefix-based
filtering.
Purpose Refer to below procedure for route filtering by means of
AS_PATH configuration on ZTE ZXR10 GER.
Prerequisite
Steps 1. To configure route filtering by means of AS_PATH, use ip as-
E
ND OF STEPS
Example: As shown in Figure 98 , router filtering based on AS
path also can be used so that R1 will not advertise the network
192.18.10.0/24 from AS300 to AS200. The configuration is as
follows:
Router Command Line Interface has been accessed.
BGP is running on a network.
path access-list
<as-regular-expression> command in global config mode as
shown in Table 292.
T 2 9 2 I A - P
A B L E P S A T H
Command Format
ip as-path access-list
<access-list-number>
{permit|deny} <as-
regular-expression>
Result: This configures an ip as-path access list.
Confidential and Proprietary Information of ZTE CORPORATION
Chapter 16 BGP Configuration
<access-list-number>
A - L C
C C E S S I S T O M M A N D
Command
Mode
Global
{permit|deny}
Command
Function
This defines BGP
access list
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