Ospf Help please

Hi i was just setting up a basic lab and im not getting any OSPF neighbors when try to run ospf on 2 routers.

Below is my debug, can anyone help me decipher this and point me in the right direction where to look???

%LINK-5-CHANGED: Interface Vlan1, changed state to administratively down

00:00:10: OSPF: Interface FastEthernet0/0 going Up

00:00:10: OSPF: Build router LSA for area 0, router ID 1.1.1.1, seq 0x80000001

%SYS-5-CONFIG_I: Configured from console by console

%LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0/0, changed state to up

00:00:50: OSPF: end of Wait on interface FastEthernet0/0

00:00:50: OSPF: DR/BDR election on FastEthernet0/0

00:00:50: OSPF: Elect BDR 1.1.1.1

00:00:50: OSPF: Elect DR 1.1.1.1

00:00:50: OSPF: Elect BDR 0.0.0.0

00:00:50: OSPF: Elect DR 1.1.1.1

00:00:50: DR: 1.1.1.1 (Id) BDR: none

00:00:50: OSPF: Build router LSA for area 0, router ID 1.1.1.1, seq 0x80000002

00:00:50: OSPF: No full nbrs to build Net Lsa for interface FastEthernet0/0

any help would be great cheers

Dan

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Comments

NetworkVeteran

DANMOH009 wrote: »

Below is my debug, can anyone help me decipher this and point me in the right direction where to look???

The router in question doesn't see any other OSPF-speaker on the interface.

L3 connectivity requires checking (ip, ping).
L2 connectivity requires checking (interface vlan configuration).
L1 connectivity seems fine (link up messages).

veritas_libertas

Post your running-config for both of the routers.

DANMOH009

its a very basic lab im doin in PT-

just 2 routers at first i thought its because maybe its a it looks like a point-to-point connection, but that cant be its part of a lab and the whole purpose is to advertise the networks attached.

ping also works fine between the serial link connecting the 2 routers

DANMOH009

router 1

hostname Ranet-BR
!
!
!
!
!
!
!
!
!
!
!
!
ip name-server 0.0.0.0
!
!
!
!
!
!
interface FastEthernet0/0
ip address 128.0.6.150 255.255.255.248
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
ip address 128.0.6.157 255.255.255.252
clock rate 64000
!
interface Vlan1
no ip address
shutdown
!
router ospf 100
router-id 1.1.1.1
log-adjacency-changes
network 128.0.6.156 0.0.0.3 area 0
network 128.0.6.144 0.0.0.7 area 0
!
ip classless
!
!
!
!
!
!
!
line con 0
line vty 0 4
login

router 2

hostname Ranet-HQ
!
!
!
!
!
!
!
!
!
!
!
!
ip name-server 0.0.0.0
!
!
!
!
!
!
interface FastEthernet0/0
ip address 128.0.6.142 255.255.255.240
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
ip address 128.0.6.157 255.255.255.252
!
interface Serial0/1/0
ip address 128.0.6.94 255.255.255.252
!
interface Vlan1
no ip address
shutdown
!
router ospf 1
router-id 1.1.0.1
log-adjacency-changes
network 128.0.6.92 0.0.0.3 area 0
network 128.0.6.128 0.0.0.15 area 0
!
ip classless
!
!
!
!
!
!
!
line con 0
line vty 0 4
login

DANMOH009

ahhh the ips are the same!!!!

DANMOH009

that didnt fix it its still not working??

i changed the ip on the serial

new sh run

hostname Ranet-BR
!
!
!
!
!
!
!
!
!
!
!
!
ip name-server 0.0.0.0
!
!
!
!
!
!
interface FastEthernet0/0
ip address 128.0.6.150 255.255.255.248
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
duplex auto
speed auto
shutdown
!
interface Serial0/0/0
ip address 128.0.6.158 255.255.255.252
clock rate 64000
!
interface Vlan1
no ip address
shutdown
!
router ospf 100
router-id 1.1.1.1
log-adjacency-changes
network 128.0.6.156 0.0.0.3 area 0
network 128.0.6.144 0.0.0.7 area 0
!
ip classless
!
!
!
!
!
!
!
line con 0
line vty 0 4
login

NetworkVeteran

I can see the issue, but I'd rather you worked your way through it.

Okay. You say you fixed the IP mismatch.

Did you verify ping works across each interface you want OSPF to talk across? Reverify if you need to. Shoddy verification at one layer can lead to hours of time wasted.

OSPF runs over IP. Let's focus on it next.

Did you verify OSPF is working across each interface you want it to? Try it on both devices. Note which interfaces are talking / not talking, and any problems they face.

lantech

Try checking your configs again. I think you have another config error in there. Did you run your debug on the other router as well?

Think about how OSPF works and what's needed for it to work. Are the routers forming a neighbor relationship to begin with?

Zartanasaurus

sh ip ospf int br
sh ip ospf nei

DANMOH009

Its a timed lab of 30 mins.

So I have to do it again, as it expired yesterday.

I'll try it again tonight and verify just in case the problems the same.

AHHH..............

I'VE NOT ADVERTISED THE NETWORK - network 128.0.6.156 0.0.0.3 area 0 on the Ranet-BR router is that right???

lantech

Is this in packet tracer?

If so just create the topology and try the lab again. Then you won't be timed.

I believe that's it.

Ltat42a

In the Activity window, click "Check Results", then click "Assessment Items", it will show you what's missing.

hth

lantech

Ltat42a wrote: »

In the Activity window, click "Check Results", then click "Assessment Items", it will show you what's missing.
hth

Hey now, that's cheating. Besides, he won't have an activity window when he is out in the real world.

xXErebuS

!
interface Serial0/0/0
ip address 128.0.6.157 255.255.255.252
!
interface Serial0/1/0
ip address 128.0.6.94 255.255.255.252
!
interface Vlan1
no ip address
shutdown
!
router ospf 1
router-id 1.1.0.1
log-adjacency-changes
network 128.0.6.92 0.0.0.3 area 0
network 128.0.6.128 0.0.0.15 area 0

This is where your error is (atleast part of it). Remember OSPF/EIGRP network commands specify what interfaces participate, not what networks to advertise.

DANMOH009

Finally got it working, thanks for your help everyone. Ended up having to watch the CBT video again, but learnt from my mistakes

Cheers