OSPF problem...

hi guys, this is a topo set up. Routing protocol is OSPF. However following observations were made.

router_1 cannot ping router_4
Router_4 cannot ping router_1 and router_2
router_2 and router_3 can ping all the other routers.

in the routing tables of the 4 routers i noticed this entry common (but with different timings):-

O 255.254.254.255 [110/0] via , 00:37:13,

What does this entry indicate ??
How did this entry creep in...is this y i am encountering connectivity problems among the routers ??

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Comments

Netstudent

is that the only entry in the table? it seems like you can only ping directly connected neighbors in which case would mean you have no routes. post the runingconfigs so we can see the OSPF process configuration.

live_wire

no...it is present along with other entries.

router_1 table has an entry for 30.0.0.0 network, yet cant ping router 4
router_4 table has no entry for 10.0.0.0 or 20.0.0.0 network
router_2 and router_3 hav all the required correct entries

and the phantom entry is present in all the router's routing table

Netstudent

can you copy and paste the running-configs? also if this is boson, I wouldn;t be surprised if it was a bigtme bug. if router4 has no entry, then the echo reply doesn;t know where to go when you ping 4.

live_wire

i m srry ..i cant, Boson does not allow my to even select the text..let alone copy/paste.

i l try to take a screen shot, but it will b too long with 4 routers, if u say so,i will

Netstudent

it does copy, you just can't see the highlited text. try dragging your cursor even though you can't see the highlite. then copy it or ctrl+c.

if 1 can ping 3, then the problem is router4

try giving router4 a default route with r3's interface as the next hop. If that solves the problem, then you need to double check your config on r4

live_wire

router_1 config

router_1#sh run
Building configuration...

!
Version 12.1
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname router_1
!
!
!
ip subnet-zero
!
!
!
!
!
!
!
interface Loopback0
ip address 50.0.0.1 255.0.0.0
no ip directed broadcast
!
interface Serial0
ip address 10.0.0.1 255.0.0.0
no ip directed-broadcast
clock rate 64000
backup interface
!
interface Serial1
no ip address
no ip directed-broadcast
backup interface
shutdown
!
interface Ethernet0
no ip address
no ip directed-broadcast
bandwidth 10000
backup interface
no fair-queue
shutdown
!
interface Bri0
no ip address
no ip directed-broadcast
backup interface
no fair-queue
shutdown
!
!
router ospf 100
network 10.0.0.0 0.255.255.255 area 0
!
ip classless
no ip http server
!
!
!
line con 0
transport input none
line aux 0
line vty 0 4
!
no scheduler allocate
end

----router_2 config

router_2#sh runn
Building configuration...

!
Version 12.1
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname router_2
!
!
!
ip subnet-zero
!
!
!
!
!
!
!
interface Loopback0
ip address 60.0.0.1 255.0.0.0
no ip directed broadcast
!
interface Serial0
ip address 20.0.0.1 255.0.0.0
no ip directed-broadcast
clock rate 64000
backup interface
!
interface Serial1
ip address 10.0.0.2 255.0.0.0
no ip directed-broadcast
backup interface
!
interface Ethernet0
no ip address
no ip directed-broadcast
bandwidth 10000
backup interface
no fair-queue
shutdown
!
interface Bri0
no ip address
no ip directed-broadcast
backup interface
no fair-queue
shutdown
!
!
router ospf 100
network 10.0.0.0 0.255.255.255 area 0
network 20.0.0.0 0.255.255.255 area 0
!
ip classless
no ip http server
!
!
!
line con 0
transport input none
line aux 0
line vty 0 4
!
no scheduler allocate
end

router_3

router_3#sh run
Building configuration...

!
Version 12.1
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname router_3
!
!
!
ip subnet-zero
!
!
!
!
!
!
!
interface Loopback0
ip address 70.0.0.1 255.0.0.0
no ip directed broadcast
!
interface Serial0
ip address 30.0.0.1 255.0.0.0
no ip directed-broadcast
clock rate 64000
backup interface
!
interface Serial1
ip address 20.0.0.2 255.0.0.0
no ip directed-broadcast
backup interface
!
interface Ethernet0
no ip address
no ip directed-broadcast
bandwidth 10000
backup interface
no fair-queue
shutdown
!
interface Bri0
no ip address
no ip directed-broadcast
backup interface
no fair-queue
shutdown
!
!
router ospf 100
network 20.0.0.0 0.255.255.255 area 0
network 30.0.0.0 0.255.255.255 area 0
!
ip classless
no ip http server
!
!
!
line con 0
transport input none
line aux 0
line vty 0 4
!
no scheduler allocate
end

router_4

router_4#sh run
Building configuration...

!
Version 12.1
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname router_4
!
!
!
ip subnet-zero
!
!
!
!
!
!
!
interface Loopback0
ip address 90.0.0.1 255.0.0.0
no ip directed broadcast
!
interface Serial0
no ip address
no ip directed-broadcast
backup interface
shutdown
!
interface Serial1
ip address 30.0.0.2 255.0.0.0
no ip directed-broadcast
backup interface
!
interface Ethernet0
no ip address
no ip directed-broadcast
bandwidth 10000
backup interface
no fair-queue
shutdown
!
interface Bri0
no ip address
no ip directed-broadcast
backup interface
no fair-queue
shutdown
!
!
router ospf 100
network 30.0.0.0 0.255.255.255 area 0
!
ip classless
no ip http server
!
!
!
line con 0
transport input none
line aux 0
line vty 0 4
!
no scheduler allocate
end

thats the list ...

Netstudent

i think this is a bug in the sim. You should not have that funky address in your routing table.
I would try giving R4 a default route just to see if that helps.

live_wire

default route

# ip route 0.0.0.0 0.0.0.0 s1 // hope this is correct..( i m sure 99%, since no error prompted )
even this does not help.

also i forgot to mention earlier... if i use EIGRP..there is absolutely no problem, everything works as required.

Netstudent

ya Boson is wacky, so nothing surprises me.

live_wire

aaarrhhhh !!!!! spent 3 hours and the end result = boson is the root cause..

anyway thanx a lot mate.