3Com 8807 Configuration Manual page 389

[Switch B-Vlan-interface4] ip address 194.1.1.2 255.255.255.0
[Switch B] ospf
[Switch B-ospf-1] area 0
[Switch B-ospf-1-area-0.0.0.0] network 194.1.1.0 0.0.0.255
[Switch B-ospf-1-area-0.0.0.0] network 192.1.1.0 0.0.0.255
[Switch B] bgp 200
[Switch B-bgp] group ex external
[Switch B-bgp] peer 192.1.1.1 group ex as-number 100
[Switch B-bgp] group in internal
[Switch B-bgp] peer 194.1.1.1 group in
[Switch B-bgp] peer 195.1.1.2 group in
3 Configure Switch C:
[Switch C] interface Vlan-interface 3
[Switch C-Vlan-interface3] ip address 193.1.1.2 255.255.255.0
[Switch C] interface vlan-interface 5
[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
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Typical BGP Configuration Examples 389