confusion in bgp using ospf

oberoi

Please help me out for the is lab

here i attached all the all config of r1 r2 r3 r4 why i am not able to ping

from r2 to r3
from r1 to r4

but i can ping r3 to r2 and r4 to r1






r1

---

R1#sh run
Building configuration...


Current configuration : 1438 bytes
!
version 12.3
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R1
!
boot-start-marker
boot-end-marker
!
enable password cisco
!
no aaa new-model
ip subnet-zero
no ip icmp rate-limit unreachable
!
!
no ip domain lookup
!
ip cef
!
!
!
!
!
!
!
!
!
!
!
!
!
ip tcp synwait-time 5
!
!
!
interface Loopback0
ip address 131.108.2.1 255.255.255.0
!
interface Loopback1
ip address 131.108.3.1 255.255.255.0
!
interface Loopback2
ip address 131.108.4.1 255.255.255.0
!
interface Ethernet0/0
ip address 131.108.1.1 255.255.255.0
half-duplex
!
interface Serial0/0
ip address 131.108.255.5 255.255.255.252
clock rate 125000
!
interface Serial0/1
no ip address
shutdown
!
router ospf 1
log-adjacency-changes
network 131.108.1.0 0.0.0.255 area 0
network 131.108.2.0 0.0.0.255 area 0
network 131.108.3.0 0.0.0.255 area 0
network 131.108.4.0 0.0.0.255 area 0
!
router bgp 1
no synchronization
bgp log-neighbor-changes
network 131.108.2.0 mask 255.255.255.0
network 131.108.3.0 mask 255.255.255.0
network 131.108.4.0 mask 255.255.255.0
neighbor 131.108.1.2 remote-as 1
neighbor 131.108.255.6 remote-as 3
no auto-summary
!
no ip http server
ip classless
!
!
no cdp log mismatch duplex
!
!
!
!
!
!
line con 0
exec-timeout 0 0
privilege level 15
logging synchronous
line aux 0
exec-timeout 0 0
privilege level 15
logging synchronous
line vty 0 4
login
!
!
end


R1#

---

R2#


R2#sh run
Building configuration...


Current configuration : 1468 bytes
!
version 12.3
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R2
!
boot-start-marker
boot-end-marker
!
enable password cisco
!
no aaa new-model
ip subnet-zero
no ip icmp rate-limit unreachable
!
!
no ip domain lookup
!
ip cef
!
!
!
!
!
!
!
!
!
!
!
!
!
ip tcp synwait-time 5
!
!
!
interface Loopback0
ip address 131.108.5.1 255.255.255.0
!
interface Loopback1
ip address 131.108.6.1 255.255.255.0
!
interface Loopback2
ip address 131.108.7.1 255.255.255.0
!
interface Ethernet0/0
ip address 131.108.1.2 255.255.255.0
half-duplex
!
interface Serial0/0
ip address 131.108.255.1 255.255.255.0
clock rate 128000
!
interface Serial0/1
no ip address
shutdown
!
router ospf 1
log-adjacency-changes
network 131.108.1.0 0.0.0.255 area 0
network 131.108.5.0 0.0.0.255 area 0
network 131.108.6.0 0.0.0.255 area 0
network 131.108.7.0 0.0.0.255 area 0
!
router bgp 1
no synchronization
bgp log-neighbor-changes
network 131.108.5.0 mask 255.255.255.0
network 131.108.6.0 mask 255.255.255.0
network 131.108.7.0 mask 255.255.255.0
redistribute ospf 1 metric 100
neighbor 131.108.1.1 remote-as 1
neighbor 131.108.255.2 remote-as 2
no auto-summary
!
no ip http server
ip classless
!
!
no cdp log mismatch duplex
!
!
!
!
!
!
line con 0
exec-timeout 0 0
privilege level 15
logging synchronous
line aux 0
exec-timeout 0 0
privilege level 15
logging synchronous
line vty 0 4
login
!
!
end


R2#

---

R3#sh run
Building configuration...


Current configuration : 1037 bytes
!
version 12.3
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R3
!
boot-start-marker
boot-end-marker
!
enable password cisco
!
no aaa new-model
ip subnet-zero
no ip icmp rate-limit unreachable
!
!
no ip domain lookup
!
ip cef
!
!
!
!
!
!
!
!
!
!
!
!
!
ip tcp synwait-time 5
!
!
!
interface Ethernet0/0
ip address 141.108.1.1 255.255.255.0
half-duplex
!
interface Serial0/0
bandwidth 125
ip address 131.108.255.6 255.255.255.252
!
interface Serial0/1
ip address 131.108.255.9 255.255.255.252
!
router bgp 3
no synchronization
bgp log-neighbor-changes
network 141.108.1.0 mask 255.255.255.0
neighbor 131.108.255.5 remote-as 1
neighbor 131.108.255.10 remote-as 2
neighbor 131.108.255.10 weight 1
no auto-summary
!
no ip http server
ip classless
!
!
no cdp log mismatch duplex
!
!
!
!
!
!
line con 0
exec-timeout 0 0
privilege level 15
logging synchronous
line aux 0
exec-timeout 0 0
privilege level 15
logging synchronous
line vty 0 4
login
!
!
end

---

R4#sh run
Building configuration...


Current configuration : 998 bytes
!
version 12.3
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R4
!
boot-start-marker
boot-end-marker
!
enable password cisco
!
no aaa new-model
ip subnet-zero
no ip icmp rate-limit unreachable
!
!
no ip domain lookup
!
ip cef
!
!
!
!
!
!
!
!
!
!
!
!
!
ip tcp synwait-time 5
!
!
!
interface Ethernet0/0
ip address 151.108.1.1 255.255.255.0
shutdown
half-duplex
!
interface Serial0/0
ip address 131.108.255.2 255.255.255.252
!
interface Serial0/1
ip address 131.108.255.10 255.255.255.252
!
router bgp 2
no synchronization
bgp log-neighbor-changes
network 151.108.1.0 mask 255.255.255.0
neighbor 131.108.255.1 remote-as 1
neighbor 131.108.255.9 remote-as 3
no auto-summary
!
no ip http server
ip classless
!
!
no cdp log mismatch duplex
!
!
!
!
!
!
line con 0
exec-timeout 0 0
privilege level 15
logging synchronous
line aux 0
exec-timeout 0 0
privilege level 15
logging synchronous
line vty 0 4
login
!
!
end


R4#

DCD

This is off the subject but why are your interfaces at half duplex? Also can you put the show for BGP, OSFP and Route.

networker050184

Think what address is that icmp packet going to use as a source? Does the other router have a route to that?

daveyb

Really old topic, but this is a classic case of where to use next-hop self

pevangel

Next-hop-self is not necessary here but still a good idea. Being able to ping one way but not the other is usually an indication of not properly sourcing your pings which is what networker was hinting at. Not configuring next-hop-self would result in asymmetric routing in the OP's setup, but pings should still work as long as they are loopback to loopback.