Bgp path selection configuration, Network requirements, Configuration procedure – H3C Technologies H3C S7500E Series Switches User Manual
Page 267
6-64
The output information shows that:
z
Switch F can send route information to Switch B and Switch C through the confederation by
establishing only an eBGP connection with Switch A.
z
Switch B and Switch D are in the same confederation, but belong to different sub ASs. They
obtain external route information from Switch A and generate the same BGP route entries; it
seems like that they reside in the same AS although they have no direct connection in between.
BGP Path Selection Configuration
Network requirements
z
In the figure below, all switches run BGP. Between Switch A and Switch B, and between Switch A
and Switch C are eBGP connections. Between Switch B and Switch D, and between Switch D and
Switch C are iBGP connections.
z
OSPF is the IGP protocol in AS 200.
z
Configure routing policies, making Switch D use the route 1.0.0.0/8 from Switch C as the optimal.
Figure 6-26 Network diagram for BGP path selection configuration
Switch A
AS 100
Vlan-int101
Switch C
AS 200
Vlan-int200
Switch B
Switch D
Vlan-int100
Vlan-int200
Vlan-int400
Vlan-int400
Vlan-int300
Vlan-int300
Vlan-int100
Device Interface
IP
address
Device Interface
IP
address
Switch A
Vlan-int101
1.0.0.0/8
Switch D
Vlan-int400
195.1.1.1/24
Vlan-int100
192.1.1.1/24
Vlan-int300
194.1.1.1/24
Vlan-int200
193.1.1.1/24
Switch C
Vlan-int400
195.1.1.2/24
Switch B
Vlan-int100
192.1.1.2/24
Vlan-int200 193.1.1.2/24
Vlan-int300
194.1.1.2/24
Configuration procedure
1) Configure IP addresses for interfaces (omitted).
2) Configure OSPF on Switch B, C, and D.
# Configure Switch B.
[SwitchB] ospf
[SwitchB-ospf] area 0
[SwitchB-ospf-1-area-0.0.0.0] network 192.1.1.0 0.0.0.255
[SwitchB-ospf-1-area-0.0.0.0] network 194.1.1.0 0.0.0.255
[SwitchB-ospf-1-area-0.0.0.0] quit
[SwitchB-ospf-1] quit
# Configure Switch C.
[SwitchC] ospf