BGP Ping test

Please help,

From R1, i can ping the loopback IP(3.3.3.3) that was advertised via BGP. But from R3 cant ping the loopback IP's of the R1 that was advertise via BGP.

R1 ----EBGP---- R2

IBGP

R3

Kinly see below config:

R1
interface Loopback0
ip address 2.2.2.2 255.255.255.255
!
interface Loopback1
ip
address 192.168.1.1 255.255.255.255
!
interface Loopback2
ip address 192.168.1.2 255.255.255.255
!
interface Loopback3
ip address 192.168.1.3 255.255.255.255
!
interface Loopback4
ip address 192.168.1.4 255.255.255.255
!
interface Loopback5
ip address 192.168.1.5 255.255.255.255
!
interface GigabitEthernet1/0
ip address 10.0.1.1 255.255.255.252
negotiation auto
!
router bgp 100
no synchronization
bgp log-neighbor-changes
redistribute connected route-map LOOPBACKS
neighbor 4.4.4.4 remote-as 200
neighbor 4.4.4.4 ebgp-multihop 2
neighbor 4.4.4.4 update-source Loopback0
no auto-summary
!
ip access-list standard LOOPBACKS
permit 192.168.1.0 0.0.0.255
!
route-map LOOPBACKS permit 10
match ip address LOOPBACKS
!

R2
interface Loopback0
ip address 4.4.4.4 255.255.255.255
!
interface GigabitEthernet1/0
ip address 10.0.1.2 255.255.255.252
negotiation auto
!
interface GigabitEthernet2/0
ip address 10.0.1.5 255.255.255.252
negotiation auto
!
router ospf 1
log-adjacency-changes
redistribute static subnets
network 4.4.4.4 0.0.0.0 area 0
network 10.0.1.0 0.0.0.3 area 0
network 10.0.1.4 0.0.0.3 area 0
!
router bgp 200
no synchronization
bgp log-neighbor-changes
neighbor 2.2.2.2 remote-as 100
neighbor 2.2.2.2 ebgp-multihop 2
neighbor 2.2.2.2 update-source Loopback0
neighbor 3.3.3.3 remote-as 200
neighbor 3.3.3.3 update-source Loopback0
no auto-summary
!

R3
interface Loopback0
ip address 3.3.3.3 255.255.255.255
!
interface GigabitEthernet2/0
ip address 10.0.1.6 255.255.255.252
negotiation auto
!
router bgp 200
no synchronization
bgp log-neighbor-changes
redistribute connected route-map LOOPBACK
neighbor 4.4.4.4 remote-as 200
neighbor 4.4.4.4 update-source Loopback0
no auto-summary
!
route-map LOOPBACK permit 10
match ip address LOOPBACK
!
ip access-list standard LOOPBACK
permit 3.3.3.3
!

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Comments

late_collision

At first glance, it looks like you need to permit 2.2.2.2 in your LOOPBACKS access-list on R1

edubillo

Thanks for the help Sir!

After permitting the 2.2.2.2, the loopbacks from R1 still cannot ping. Also I can ping the 2.2.2.2 using redistribute static under OSPF.

Please help

networker050184

Look at what source your ping is using.

t3mp

late_collision wrote: »

At first glance, it looks like you need to permit 2.2.2.2 in your LOOPBACKS access-list on R1

late_collision, we don't need "permit 2.2.2.2 in your LOOPBACKS" because then we advertise 2.2.2.2/32 via eBGP to R2 it's not best in BGP table, cause of exist static route point to 2.2.2.2 via R1. Therefore we don't advertise this route to any peer on R2. Also R3 have route to 2.2.2.2/32, via ospf, "redistribute static subnets" on R2.

edubillo, from you config, i'm don't see route connected of network on R2,R3 10.0.1.4/30 advertised to R1. You can add this on R2 like:
router bgp 200
network 10.0.1.4 mask 255.255.255.252

And them:
R3# ping 2.2.2.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 2.2.2.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/1 ms

Because ping in this case use source IP: 10.0.1.6.