HP 6125G HP 6125G & 6125G/XG Blade Switches Layer 3 - IP Routing Confi - Page 187

BGP path selection configuration example, Network requirements, Configuration procedure

Page 187 highlights

From : 10.1.3.1 (1.1.1.1) Relay Nexthop : 0.0.0.0 Original nexthop: 10.1.3.1 AS-path : 100 Origin : igp Attribute value : MED 0, localpref 100, pref-val 0, pre 255 State : valid, internal, best, Not advertised to any peers yet The output shows the following: { Switch F can send route information to Switch B and Switch C through the confederation by establishing only an EBGP connection with Switch A. { 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 they reside in the same AS although they have no direct connection in between. BGP path selection configuration example Network requirements In Figure 68, 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. OSPF is the IGP protocol in AS 200. Configure routing policies, making Switch D use the route 1.0.0.0/8 from Switch C as the optimal. Figure 68 Network diagram AS 200 Vlan-int101 AS 100 Vlan-int100 Vlan-int200 Switch A Vlan-int100 Vlan-int300 Switch B Vlan-int300 Vlan-int400 Switch D Vlan-int200 Vlan-int400 Switch C Device Switch A Switch B Interface Vlan-int101 Vlan-int100 Vlan-int200 Vlan-int100 Vlan-int300 IP address 1.0.0.0/8 192.1.1.1/24 193.1.1.1/24 192.1.1.2/24 194.1.1.2/24 Device Switch D Switch C Interface Vlan-int400 Vlan-int300 Vlan-int400 Vlan-int200 IP address 195.1.1.1/24 194.1.1.1/24 195.1.1.2/24 193.1.1.2/24 Configuration procedure 1. Configure IP addresses for interfaces. (Details not shown.) 2. Configure OSPF on Switch B, C, and D: # Configure Switch B. system-view 177

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177
From
: 10.1.3.1 (1.1.1.1)
Relay Nexthop
: 0.0.0.0
Original nexthop: 10.1.3.1
AS-path
: 100
Origin
: igp
Attribute value : MED 0, localpref 100, pref-val 0, pre 255
State
: valid, internal, best,
Not advertised to any peers yet
The output shows the following:
{
Switch F can send route information to Switch B and Switch C through the confederation by
establishing only an EBGP connection with Switch A.
{
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 they reside in the same AS although they have no direct connection in between.
BGP path selection configuration example
Network requirements
In
Figure 68
, 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. OSPF is the IGP protocol in AS 200.
Configure routing policies, making Switch D use the route 1.0.0.0/8 from Switch C as the optimal.
Figure 68
Network diagram
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. (Details not shown.)
2.
Configure OSPF on Switch B, C, and D:
# Configure Switch B.
<SwitchB> system-view
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