Bgp Community Configuration - 3Com MSR 50 Series Configuration Manual

864 C 56: BGP C
HAPTER ONFIGURATION
BGP Community
Configuration
[RouterB] bgp 65009
[RouterB-bgp] default med 100
# Display BGP routing table information on Router A.
[RouterA] display bgp routing-table
Total Number of Routes: 3
BGP Local router ID is 1.1.1.1
Status codes: * - valid, > - best, d - damped,
h - history,
Origin : i - IGP, e - EGP, ? - incomplete
Network
*> 8.0.0.0
*> 9.1.1.0/24
*
From the above information, you can find the route with the next hop 200.1.2.1 is
the best route, because its MED (0) is smaller than the MED (100) of the other
route with the next hop 200.1.1.1 (Router B).
Network requirements
Router B establishes EBGP connections with Router A and Router C. Configure
No_Export community attribute on Router A to make routes from AS 10 not
advertised by AS 20 to any other AS.
Network diagram
Figure 249 Network diagram for BGP community configuration
200 .1.2 .1/24
EBGP
S2/1
200.1.2.2/24
S2/2
200.1.3.1/24
AS 20
Router B
Configuration procedure
1 Configure IP addresses for interfaces (omitted)
2 Configure EBGP connections.
# Configure Router A.
<RouterA> system-view
[RouterA] bgp 10
[RouterA-bgp] router-id 1.1.1.1
[RouterA-bgp] peer 200.1.2.2 as-number 20
[RouterA-bgp] network 9.1.1.0 255.255.255.0
[RouterA-bgp] quit
i - internal, s - suppressed, S - Stale
NextHop MED
0.0.0.0 0
200.1.2.1 0
200.1.1.1 100
Eth1/0
9.1.1.1 /24
S2 /1
AS 10
Router A
EBGP
S2/2
200.1.3.2/24
Router C
LocPrf PrefVal Path/Ogn
0 i
0 65009i
0 65009i
AS 30