Prerequisites: CCNP level skills.
Topology
Task 1
Configure EBGP session between R1 and R4. R4 should advertise an aggregate 172.16.0.0 instead of individual subnets. Do not use 'aggregate-address' command to accomplish this.
Lab Solution
Task 1
Configure EBGP session between R1 and R4. R4 should advertise an aggregate 172.16.0.0 instead of individual subnets. Do not use 'aggregate-address' command to accomplish this.
R1 Configuration:
!
router bgp 10
no synchronization
bgp router-id 1.1.1.1
bgp log-neighbor-changes
neighbor 10.1.124.4 remote-as 40
no auto-summary
no synchronization
bgp router-id 1.1.1.1
bgp log-neighbor-changes
neighbor 10.1.124.4 remote-as 40
no auto-summary
!
R4 Configuration:
!
router bgp 40
no synchronization
bgp router-id 4.4.4.4
bgp log-neighbor-changes
network 172.16.0.0
neighbor 10.1.124.1 remote-as 10
auto-summary
no synchronization
bgp router-id 4.4.4.4
bgp log-neighbor-changes
network 172.16.0.0
neighbor 10.1.124.1 remote-as 10
auto-summary
!
Notice!
BGP 'auto-summary' command allows to use a classful 'network' statement (contrary to the situation when auto-summary is disabled). Also, when redistributing subnets into BGP, auto-summary is going to install and advertise them as classful networks.
Verification:
Pic. 2 - BGP Table on R1.
