H3C S7500 Series Ethernet Switches Release 3135 DHCP Configuration Examples

Routing Configuration Examples
H3C S7500 Series Ethernet Switches Release 3135 Chapter 2 Configuration Examples
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2.1.8 BGP Path Selection Configuration Example
I. Network requirements
1) Requirement analysis
A network consists of two ASs, which run BGP to communicate with each other. OSPF
runs in one of them.
The requirement is to control the data forwarding path from AS 200 to AS 100.
The following give two plans to meet the requirement
z Use the MED attribute to control the forwarding path for packets from AS 200 to
AS 100.
z Use the LOCAL_PREF attribute to control the forwarding path for packets from AS
200 to AS 100
2) Network diagram
Figure 2-8 shows the network diagram.
Device Interface IP address AS
Switch A Vlan-int 101 1.1.1.1/8
Vlan-int 2 192.1.1.1/24
Vlan-int 3 193.1.1.1/24
100
Switch B Vlan-int 2 192.1.1.2/24
Vlan-int 4 194.1.1.2/24
Switch C Vlan-int 3 193.1.1.2/24
Vlan-int 5 195.1.1.2/24
Switch D Vlan-int 4 194.1.1.1/24
Vlan-int 5 195.1.1.1/24
200
Figure 2-8 Network diagram for BGP path selection
3) Configuration plan
z Run EBGP between AS 100 and AS 200. Advertise network 1.0.0.0/8.
z Run OSPF in AS 200 to realize network interconnection.
z Run IBGP between Switch D and Switch B as well as between Switch D and
Switch C.
z Apply a routing policy on Switch A to modify the MED attribute of the route to be
advertised to AS 200, making the data forwarding path from Switch D to AS 100 as
Switch D – Switch C – Switch A.