Filtering Routes Through Route Map; Filtering Routes Through Nlri - Zte ZXR10 8900 Series User Manual

Step Command
1 router bgp <as-number>
ZXR10(config)#
2
ZXR10(config-router)#
route-map <map-tag>{in|out}
3
ZXR10(config-router)#
|deny][<sequence-number>]
Example
Example

Filtering Routes through Route Map

Route filtering and attribute setting are the basis of BGP route
selection. Input or output route attributes can be controlled as
required by route filtering.
Route map is used to control routing information and re-distribute
routes between route domains based on defined conditions. Route
map usually determines route selections with the use of route at-
tributes.
To filter routes through route map, perform the following steps.
neighbor <ip-address>
route-map <map-tag>[permit
This example shows how to filter routes through route map.
ZXR10_R1(config)#router bgp 100
ZXR10_R1(config-router)#neighbor 182.17.20.1 remote-as 200
ZXR10_R1(config-router)#neighbor 182.17.20.1 route-map MAP1 out
ZXR10_R1(config-router)#neighbor 182.17.20.1 send-med
ZXR10_R1(config)#route-map MAP1 permit 10
ZXR10_R1(config-route-map)#match ip address 1
ZXR10_R1(config-route-map)#set metric 5
ZXR10_R1(config)#acl standard number 1
ZXR10_R1(config-std-acl)#rule 1 permit 172.3.0.0 0.0.255.255
The above configuration defines a route map MAP1, which allows
network 172.3.0.0 to be advertised to autonomous system 200
and sets the MED value to 5. When filtering routes through route
map, match and set commands are both usually used. The m
atch command defines matching criteria. The set command de-
fines actions to be executed when the match conditions are satis-
fied.

Filtering Routes through NLRI

To restrict a router from obtaining or advertising routing informa-
tion, route updates from or to a special neighbor device can be fil-
tered. A filter contains an update list from or to a neighbor router.
As shown in Figure 17, R1 and R2 are mutually IBGP peers, R1 and
R3 are mutually EBGP peers, and R4 and R2 are mutually EBGP
peers.
Confidential and Proprietary Information of ZTE CORPORATION
Chapter 6 BGP Configuration
Function
This starts BGP process
This configures filtration of
routes advertised by or to the
neighbors
This defines a route map
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