OSPF routes not updating

[Brian AD]

I am running a lab environment where I am trying to use OSPF on three Cisco 2960 routers.  Routers are connected via serial interface (s0/0/0 on 1 router connects to s0/0/1 on another router, s0/0/0 on each router is the DCE and has clockrate configured).  All IP Addresses and subnet masks have been verified as accurate.  All interfaces have protocol and status as 'up'.  However, no routes are being distributed via OSPF.  Original OSPF commands listed below:

Rtr (config)#  router ospf 10

Rtr (config-router)#  network 172.16.1.5 0.0.0.3 area 0    (router to router link using s0/0/0)

Rtr (config-router)#  network 172.16.1.14 0.0.0.3 area 0    (router to router link using s0/0/1)

Rtr (config-router)#  network 192.168.1.1 0.0.0.63 area 0    (router to internal network link using fa0/0)

Similar configurations are on all three routers.  This setup works great in Packet Tracer, but I cannot get it to work in the actual lab.

Being a newbie (and already spending about 5 hours on this issue), what steps am I missing to complete the OSPF configuration?

Thank you in advance,

Brian (MIS instructor)

[balaji.bandi]

This setup works great in Packet Tracer, but I cannot get it to work in the actual lab.

what do you mean actual lab, real gear you mean ?

i would check is the interface OSPF enabled ? are you able to ping each other , enable ospf debug and see what error you getting ?

post from all routers -

show run

show ip route

show ip interface brief

show cdp neigh

show ip ospf interface

show ip ospf neigh

[Brian AD]

Yes, I have a physical networking lab with real devices (see the image below) that I use for teaching at a University.  I cannot ping across networks.  I can ping the router interfaces from an attached workstation on the local or attached network, but the workstations cannot ping the remote routers or networks (destination not reachable)Lab Topology.  I am unable to ping any interfaces from within any of the routers, including their own interfaces.

I am compiling the outputs now.  Though I am seeing that there are no OSPF neighbors when I run the

show IP ospf neighbor

command.  Below are the outputs from one of the routers (all are returning similar values).

Router Outputs (Router on network B in the above diagram):

RtrB Show CDP Neighbor

RTRB Show IP OSPF Interface

RtrB Show IP OSPF Neighbor

RtrB Show Run, Part 1RtrB Show Run, Part 2  

[MHM Cisco World]

no | default] ip ospf lls [disable] 

disable lls in all router 
and then check the OSPF

[David Ruess]

Can you share the exact same output from one other router?

What IPs are you using for each LAN interface? If they are the same problems will be 2-fold.  Since that's the highest IP it will use that as its Router ID and OSPF wont exchange neighborship with a neighbor with the same RID. And each router will claim to have that LAN network and never route to any of the others because the local route will always win.

-David

[Brian AD]

The IP Addressing scheme I am using is:

Network A
Router:  Interface fa0/0 - 192.168.1.1/26
Computer 1:  192.168.1.20/26 (standard workstation)
Computer 2:  192.168.1.10/26 (using as a web server

Network B
Router:  Interface fa0/0 192.168.1.65/26
Computer 1:  192.168.1.80/26

Network C
Router:  Interface fa0/0 192.168.1.129/26
Computer 1:  192.168.1.150/26

Router to Router
RtrA s0/0/0:  172.16.1.13/30 connects to RtrB s0/0/1:  172.16.1.14/30  (I had originally used .1 and .2, but wondered about network address issues)
Rtr B s0/0/0:  172.16.1.5/30 connects to RtrC s0/0/1:  172.16.1.6/30
Rtr C s0/0/0:  172.16.1.9/30 connects to RtrA s0/0/1:  172.16.1.10/30

[David Ruess]

Hello,

Make sure you can ping your directly connected neighbors - if they cant reach eachother no neighborships form. 

Can you provide the config and topology diagram of the setup?

Also you network statements look unconventional.

It could be possible your not encompassing your interfaces in the OSPF process. It looks like you're trying to use the interface IP exactly but use a wildcard mask that is not single IP friendly.

If you re specifying the exact interface IP the wildcard mask needs to be 0.0.0.0 so your below statements would look like:

Rtr (config-router)#  network 172.16.1.5 0.0.0.0 area 0  

Rtr (config-router)#  network 172.16.1.14 0.0.0.0 area 0  

Rtr (config-router)#  network 192.168.1.1 0.0.0.0 area 0 

Your statements fall under different subnets I think. The first example:

network 172.16.1.5 0.0.0.3 area 0

Only covers interfaces with an IP address of 172.16.1.1/172.16.1.2 - if your interface is 172.16.1.5 that wont be covered. The rest follow the same suit.

-David

[Brian AD]

I cannot ping neighbors and I have verified that no neighborships are forming (see diagram):

RtrA OSPF Neighbors - same on all routers

So when assigning the networks in the OSPF configuration, should I use the IP network address with the wildcard mask?  So something like: 

network 172.16.1.8 0.0.0.3 area 0

 or is it better to use the interface IP address (172.16.1.10 0.0.0.0), the interface itself (s/0/0/0), or the remote router's interface IP Address (172.16.1.9 0.0.0.3)?  I understand IP Addressing pretty well, but this Cisco stuff is very new to me.

[David Ruess · Accepted solution]

If you want exact control you would do the exact interface IP of the local router with all 0s for the wildcard mask.

Try the following:

Under the serial interface connecting to a router enter the command below:

interface s0/0/1

ip ospf 10 area 0

Then go to the neighbor router and configure the same thing on the Serial interface connecting the one you just configured.

Yeah you wont even start a neighborship until the routers have basic connectivity to their neighbors.

-David

[Brian AD]

So when setting the process ID, I need to have the same process-id value on the two connected interfaces?  Does each pair of interfaces need a separate process-id value?  So I would run the

ipospf 10 area 0

command on router 1 s0/0/0 and router 2 s0/0/1, then run 

ip ospf 20 area 0

on router 2 s0/0/0 and router 3 s0/0/1, then 

ip ospf 30 area 0

on router 3 s0/0/0 and router 1 s0/0/1? (in this scenario, s0/0/0 is always the DCE port, and s0/0/1 is always DTE).

[David Ruess]

You need the same process ID on the device as a whole. So R1 will have the process ID of 10 on ALL interfaces. If you use different process IDs on the same device then you will need to redistribute. Each router can have different process IDs though and it will work fine. So the link doesnt need to have the same process ID on each side, if that makes sense.

[MHM Cisco World]

if

ip ospf x area x 

solve your issue then sure there are something wrong in your subnet in your interface. 
check each subnet using online subnet calcualtor 

[MHM Cisco World]

can you share two routers config ?
are there any ACL apply to interface ?

[Brian AD]

There are no ACLs, that I am aware of.  When you ask for the config, is that the

show run command 

output (included below).

RtrA Show Run, Part 1

RtrA Show Run, Part 2

RtrB Show Run, Part 1

RtrB Show Run, Part 2

[MHM Cisco World]

no | default] ip ospf lls [disable] 

disable lls in all router 
and then check the OSPF