H3C S9500 Series Operation Manual page 146

Operation Manual – BGP
H3C S9500 Series Routing Switches
[Switch C-Vlan-interface5] ip address 195.1.1.2 255.255.255.0
[Switch C] ospf
[Switch C-ospf-1] area 0
[Switch C-ospf-1-area-0.0.0.0] network 193.1.1.0 0.0.0.255
[Switch C-ospf-1-area-0.0.0.0] network 195.1.1.0 0.0.0.255
[Switch C] bgp 200
[Switch C-bgp] group ex external
[Switch C-bgp] peer 193.1.1.1 group ex as-number 100
[Switch C-bgp] group in internal
[Switch C-bgp] peer 195.1.1.1 group in
[Switch C-bgp] peer 194.1.1.2 group in
4) Configure Switch D.
[Switch D] interface vlan-interface 4
[Switch D-Vlan-interface4] ip address 194.1.1.1 255.255.255.0
[Switch D] interface vlan-interface 5
[Switch D-Vlan-interface5] ip address 195.1.1.1 255.255.255.0
[Switch D] ospf
[Switch D-ospf-1] area 0
[Switch D-ospf-1-area-0.0.0.0] network 194.1.1.0 0.0.0.255
[Switch D-ospf-1-area-0.0.0.0] network 195.1.1.0 0.0.0.255
[Switch D-ospf-1-area-0.0.0.0] network 4.0.0.0 0.255.255.255
[Switch D] bgp 200
[Switch D-bgp] group ex external
[Switch D-bgp] peer ex as-number 200
[Switch D-bgp] peer 195.1.1.2 group ex
[Switch D-bgp] peer 194.1.1.2 group ex
To enable the configuration, all BGP neighbors will be reset using the reset bgp all
command.
After above configuration, due to the fact that the MED attribute of route 1.0.0.0
discovered by Switch C is less than that of Switch B, Switch D will first select the route
1.0.0.0 from Switch C.
If the MED attribute of Switch A is not configured, the local preference on Switch C is
configured as follows:
# Configure the local preference attribute of Switch C.
Add ACL 2000 on Switch C and permit network 1.0.0.0.
[Switch C] acl number 2000
[Switch C-acl-basic-2000] rule permit source 1.0.0.0 0.255.255.255
[Switch C-acl-basic-2000] rule deny source any
Define a route policy named Localpref, and set the local preference of routes matching
ACL 2000 to 200, and that of routes not matching to 100.
[Switch C] route-policy localpref permit node 10
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Chapter 1 BGP Configuration