The document provides the configuration steps for a lab exercise on BGP. The steps include: 1. Configuring IBGP and EBGP neighborships between routers as shown in the topology diagram using loopback addresses. 2. Advertising loopback networks in BGP to ensure all routers have the routing information. 3. Configuring route reflectors to reduce the number of neighbor relationships needed. 4. Setting preferences for best paths between routers for certain networks.

1. LAB 11: BGP
Task
1. Configure IP Addresses as per given in topology.
2. Configure IBGP neighborship as per given in topology. Advertise loopback 1 and loopback 2 in
IBGP.
3. Configure Internal BGP neighbor as per given in topology.
4. Make sure Loopback 3 and loopback 4 introduce in BGP network.
5. R3 to R7 receives all the loopback network information in BGP table. (Verify after completion of
this task).
6. Configuration Sub-AS's in BGP AS 300. Make sure R10 and R12 make neighborship with R8 and
R11.
7. Make sure R1 and R2 advertise all the loopbacks in BGP.
8. Configure EBGP neighborship as per given in topology. Make sure EBGP neighborship is configure
using loopback 1 only.
9. Make sure all routers ping loopback addresses. (Do possible Configuration)
10. On R2, Configure R14 as a best path for Network 3.3.3.0 and R8 as a best path for Network
3.3.4.0.
11. Configure weight as 1440 on R8 to make R7 as a best path for BGP routes.
12. Make sure R7 Receives metric 10000 for Network 2.2.1.0 from R3.
Figure 1 Topology

2. LAB 11: BGP
Solution
 Tasks 2: Configure IBGP neighborship as per given in topology. Advertise loopback 1 and
loopback 2 in IBGP.
R3
router eigrp 100
network 3.3.1.0 0.0.0.255
network 3.3.2.0 0.0.0.255
network 10.0.34.0 0.0.0.255
network 10.0.37.0 0.0.0.255
no auto-summary
R4
router eigrp 100
network 4.4.1.0 0.0.0.255
network 4.4.2.0 0.0.0.255
network 10.0.34.0 0.0.0.255
network 10.0.45.0 0.0.0.255
network 10.0.46.0 0.0.0.255
no auto-summary
R5
router eigrp 100
network 5.5.1.0 0.0.0.255
network 5.5.2.0 0.0.0.255
network 10.0.45.0 0.0.0.255
network 10.0.56.0 0.0.0.255
network 10.0.57.0 0.0.0.255
no auto-summary
R6
router eigrp 100
network 6.6.1.0 0.0.0.255
network 6.6.2.0 0.0.0.255
network 10.0.46.0 0.0.0.255
network 10.0.56.0 0.0.0.255
network 10.0.67.0 0.0.0.255
no auto-summary

3. LAB 11: BGP
R7
router eigrp 100
network 7.7.1.0 0.0.0.255
network 7.7.2.0 0.0.0.255
network 10.0.37.0 0.0.0.255
network 10.0.57.0 0.0.0.255
network 10.0.67.0 0.0.0.255
auto-summary
R8
router ospf 1
network 8.8.1.0 0.0.0.255 area 0
network 8.8.2.0 0.0.0.255 area 0
network 10.0.80.0 0.0.0.255 area 0
network 10.0.89.0 0.0.0.255 area 0
R9
router ospf 1
network 9.9.1.0 0.0.0.255 area 0
network 9.9.2.0 0.0.0.255 area 0
network 10.0.89.0 0.0.0.255 area 0
R10
router ospf 1
network 10.0.80.0 0.0.0.255 area 0
network 10.0.110.0 0.0.0.255 area 0
network 10.10.1.0 0.0.0.255 area 0
network 10.10.2.0 0.0.0.255 area 0
R11
router ospf 1
network 10.0.110.0 0.0.0.255 area 0
network 10.0.112.0 0.0.0.255 area 0
network 11.11.1.0 0.0.0.255 area 0
network 11.11.2.0 0.0.0.255 area 0

4. LAB 11: BGP
R12
router ospf 1
network 10.0.112.0 0.0.0.255 area 0
network 12.12.1.0 0.0.0.255 area 0
network 12.12.2.0 0.0.0.255 area 0
R13
router eigrp 200
network 10.0.134.0 0.0.0.255
network 13.13.1.0 0.0.0.255
network 13.13.2.0 0.0.0.255
no auto-summary
R14
router eigrp 200
network 10.0.134.0 0.0.0.255
network 14.14.1.0 0.0.0.255
network 14.14.2.0 0.0.0.255
no auto-summary
 Task 3: Configure Internal BGP neighbor as per given in topology. (Task 6 also complete)
R3
router bgp 1100
neighbor 10.0.34.4 remote-as 1100
neighbor 10.0.37.7 remote-as 1100
R4
router bgp 1100
neighbor 10.0.34.3 remote-as 1100
neighbor 10.0.45.5 remote-as 1100
neighbor 10.0.46.6 remote-as 1100
R5
router bgp 1100
neighbor 10.0.45.4 remote-as 1100
neighbor 10.0.56.6 remote-as 1100
neighbor 10.0.57.7 remote-as 1100

5. LAB 11: BGP
R6
router bgp 1100
neighbor 10.0.46.4 remote-as 1100
neighbor 10.0.56.5 remote-as 1100
neighbor 10.0.67.7 remote-as 1100
R7
router bgp 1100
neighbor 10.0.37.3 remote-as 1100
neighbor 10.0.57.5 remote-as 1100
neighbor 10.0.67.6 remote-as 1100
R8
router bgp 300
bgp confederation identifier 300
bgp confederation peers 600
neighbor 10.0.80.10 remote-as 600
neighbor 10.0.89.9 remote-as 300
R9
router bgp 300
neighbor 10.0.89.8 remote-as 300
R10
router bgp 600
bgp confederation identifier 300
bgp confederation peers 300
neighbor 10.0.80.8 remote-as 300
neighbor 10.0.110.11 remote-as 300
R11
router bgp 300
bgp confederation identifier 300
bgp confederation peers 600 700
neighbor 10.0.110.10 remote-as 600
neighbor 10.0.112.12 remote-as 700

6. LAB 11: BGP
R12
router bgp 700
bgp confederation identifier 300
bgp confederation peers 300
neighbor 10.0.112.11 remote-as 300
R13
router bgp 60
neighbor 10.0.134.14 remote-as 60
R14
router bgp 60
neighbor 10.0.134.13 remote-as 60
 Task 4: Make sure Loopback 3 and loopback 4 introduce in BGP network.
R3
router bgp 1100
network 3.3.3.0 mask 255.255.255.0
network 3.3.4.0 mask 255.255.255.0
R4
router bgp 1100
network 4.4.3.0 mask 255.255.255.0
network 4.4.4.0 mask 255.255.255.0
R5
router bgp 1100
network 5.5.3.0 mask 255.255.255.0
network 5.5.4.0 mask 255.255.255.0
R6
router bgp 1100
network 6.6.3.0 mask 255.255.255.0
network 6.6.4.0 mask 255.255.255.0

7. LAB 11: BGP
R7
router bgp 1100
network 7.7.3.0 mask 255.255.255.0
network 7.7.4.0 mask 255.255.255.0
R8
router bgp 300
network 8.8.3.0 mask 255.255.255.0
network 8.8.4.0 mask 255.255.255.0
R9
router bgp 300
network 9.9.3.0 mask 255.255.255.0
network 9.9.4.0 mask 255.255.255.0
R10
router bgp 600
network 10.10.3.0 mask 255.255.255.0
network 10.10.4.0 mask 255.255.255.0
R11
router bgp 300
network 11.11.3.0 mask 255.255.255.0
network 11.11.4.0 mask 255.255.255.0
R12
router bgp 700
network 12.12.3.0 mask 255.255.255.0
network 12.12.4.0 mask 255.255.255.0
R13
router bgp 60
network 13.13.3.0 mask 255.255.255.0
network 13.13.4.0 mask 255.255.255.0

8. LAB 11: BGP
R14
router bgp 60
network 14.14.3.0 mask 255.255.255.0
network 14.14.4.0 mask 255.255.255.0
 Task 5: R3 to R7 receives all the loopback network information in bgp table. (verify after
completion of this task).
R4
router bgp 1100
neighbor 10.0.34.3 route-reflector-client
neighbor 10.0.45.5 route-reflector-client
neighbor 10.0.46.6 route-reflector-client
R6
router bgp 1100
neighbor 10.0.67.7 route-reflector-client
 Task 6: Task 6 also complete in Task 3.
 Task 7: Make sure R1 and R2 advertise all the loopbacks in BGP.
R1
router bgp 100
network 1.1.1.0 mask 255.255.255.0
network 1.1.2.0 mask 255.255.255.0
network 1.1.3.0 mask 255.255.255.0
network 1.1.4.0 mask 255.255.255.0
R2
router bgp 200
network 2.2.1.0 mask 255.255.255.0
network 2.2.2.0 mask 255.255.255.0
network 2.2.3.0 mask 255.255.255.0
network 2.2.4.0 mask 255.255.255.0

9. LAB 11: BGP
 Task 8: Configure EBGP Neighborship as per given in topology. Make sure EBGP neighborship is
configure using loopback 1 only.
R1
ip route 2.2.1.0 255.255.255.0 10.0.12.2
ip route 3.3.1.0 255.255.255.0 10.0.13.3
router bgp 100
neighbor 2.2.1.1 remote-as 200
neighbor 2.2.1.1 ebgp-multihop 2
neighbor 2.2.1.1 update-source Loopback1
neighbor 3.3.1.1 remote-as 1100
neighbor 3.3.1.1 ebgp-multihop 2
neighbor 3.3.1.1 update-source Loopback1
neighbor 10.0.12.2 remote-as 200
neighbor 10.0.13.3 remote-as 1100
R2
ip route 1.1.1.0 255.255.255.0 10.0.12.1
ip route 8.8.1.0 255.255.255.0 10.0.28.8
ip route 14.14.1.0 255.255.255.0 10.0.124.14
router bgp 200
neighbor 1.1.1.1 remote-as 100
neighbor 1.1.1.1 ebgp-multihop 2
neighbor 1.1.1.1 update-source Loopback1
neighbor 8.8.1.1 remote-as 300
neighbor 8.8.1.1 ebgp-multihop 2
neighbor 8.8.1.1 update-source Loopback1
neighbor 10.0.12.1 remote-as 100
neighbor 10.0.28.8 remote-as 300
neighbor 10.0.124.14 remote-as 60
neighbor 14.14.1.1 remote-as 60
neighbor 14.14.1.1 ebgp-multihop 2
neighbor 14.14.1.1 update-source Loopback1

10. LAB 11: BGP
R3
router bgp 1100
neighbor 1.1.1.1 remote-as 100
neighbor 1.1.1.1 ebgp-multihop 2
neighbor 1.1.1.1 update-source Loopback1
neighbor 10.0.13.1 remote-as 100
R5
router bgp 1100
neighbor 10.0.53.13 remote-as 60
neighbor 13.13.1.1 remote-as 60
neighbor 13.13.1.1 ebgp-multihop 2
neighbor 13.13.1.1 update-source Loopback1
R7
router bgp 1100
neighbor 8.8.1.1 remote-as 300
neighbor 8.8.1.1 ebgp-multihop 2
neighbor 8.8.1.1 update-source Loopback1
neighbor 10.0.78.8 remote-as 300
R8
router bgp 300
neighbor 2.2.1.1 remote-as 200
neighbor 2.2.1.1 ebgp-multihop 2
neighbor 2.2.1.1 update-source Loopback1
neighbor 7.7.1.1 remote-as 1100
neighbor 7.7.1.1 ebgp-multihop 2
neighbor 7.7.1.1 update-source Loopback1
neighbor 10.0.28.2 remote-as 200
neighbor 10.0.78.7 remote-as 1100
R11
router bgp 300
neighbor 10.0.114.14 remote-as 60
neighbor 14.14.1.1 remote-as 60
neighbor 14.14.1.1 ebgp-multihop 2
neighbor 14.14.1.1 update-source Loopback1

11. LAB 11: BGP
R13
router bgp 60
neighbor 5.5.1.1 remote-as 1100
neighbor 5.5.1.1 ebgp-multihop 2
neighbor 5.5.1.1 update-source Loopback1
neighbor 10.0.53.5 remote-as 1100
R14
router bgp 60
neighbor 2.2.1.1 remote-as 200
neighbor 2.2.1.1 ebgp-multihop 2
neighbor 2.2.1.1 update-source Loopback1
neighbor 10.0.114.11 remote-as 300
neighbor 10.0.124.2 remote-as 200
neighbor 11.11.1.1 remote-as 300
neighbor 11.11.1.1 ebgp-multihop 2
neighbor 11.11.1.1 update-source Loopback1
 Task 9: Make sure all routers ping loopback addresses. (Do possible Configuration)
R3
router bgp 1100
neighbor 10.0.34.4 next-hop-self
neighbor 10.0.37.7 next-hop-self
R5
router bgp 1100
neighbor 10.0.45.4 next-hop-self
neighbor 10.0.56.6 next-hop-self
neighbor 10.0.57.7 next-hop-self
R8
router bgp 300
neighbor 10.0.80.10 next-hop-self
neighbor 10.0.89.9 next-hop-self

12. LAB 11: BGP
R11
router bgp 300
neighbor 10.0.110.10 next-hop-self
neighbor 10.0.112.12 next-hop-self
R13
router bgp 60
neighbor 10.0.134.14 next-hop-self
R14
router bgp 60
neighbor 10.0.134.13 next-hop-self
(Note: verify using ping command with source address like:
)R3# ping 1.1.1.1 source l3
 Task 10: On R2, Configure R14 as a best path for Network 3.3.3.0 and R8 as a best path for
Network 3.3.4.0.
R2
access-list 10 permit 3.3.3.0 0.0.0.255
access-list 20 permit 3.3.4.0 0.0.0.255
route-map Local permit 10
match ip address 10
set local-preference 500
exit
route-map Local permit 20
exit
route-map R8 permit 21
match ip address 20
set local-preference 600
exit
route-map R8 permit 30
exit

13. LAB 11: BGP
router bgp 200
neighbor 14.14.1.1 route-map Local in
neighbor 8.8.1.1 route-map R8 in
 Task 11: Configure weight as 1440 on R8 to make R7 as a best path for BGP routes.
R8
router bgp 300
neighbor 10.0.78.7 weight 1440
 Task 12: Make sure R7 Receives metric 10000 for Network 2.2.1.0 from R3.
R7
access-list 10 permit 2.2.1.0 0.0.0.255
route-map Filter permit 10
match ip address 10
set metric 10000
exit
route-map Filter permit 20
exit
router bgp 1100
neighbor 10.0.37.3 route-map Filter in