Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Community Member

OSPF configuration

I have two routers connected by a serial cable. I have configured ospf but it's not working.

this is how I did it/;

conf t

router ospf

network 192.1.1.0 0.0.0.255 area 0

and on the other router exactly the same but different network number but the same area, my problem here is I cannot see the networks that i am advertising on the on the router and vice versa.

please help what could be a problem here?

12 REPLIES

Re: OSPF configuration

You have to configure:-

1) The IP subnet you are using for the serial link.

2) The IP Subnets you are using the either router LAN connections.

3) They must be in area 0 or you have to create a virtual tunnel to area 0.

HTH>

Community Member

Re: OSPF configuration

Do I need to do all these steps or one between them.

Please show me the first one lets say my serial ip's are 165.148.120.1/30 and .2/30 for router A and B respectively.

Re: OSPF configuration

network 165.148.120.0 0.0.0.253 area 0

Super Bronze

Re: OSPF configuration

The two routers need to share a link with OSPF. You write you're using a "different network number" on the other router. If you want to see other routes, those interfaces need to be known to OSPF.

Assuming the shared link is 192.1.1.0/24 and the first router has another interface such as 192.1.2.0/24 and the second router 192.1.3.0/24, config might look like:

first router:

router ospf

network 192.1.1.0 0.0.0.255 area 0

network 192.1.2.0 0.0.0.255 area 0

second router:

router ospf

network 192.1.1.0 0.0.0.255 area 0

network 192.1.3.0 0.0.0.255 area 0

Community Member

Re: OSPF configuration

I have tried that but I still cant see these routes on my routing table.. when I do my "sh ip route" I can't see these routes. i can only see the directly connected ones.

Re: OSPF configuration

post configs for review.

Re: OSPF configuration

use mask 255.255.255.252 for the serial link, and 255.255.255.0 for the ethernet interface networks.

Community Member

Re: OSPF configuration

If both serial interfaces are configure in a point-to-point (PPP/HDLC) configuration make sure you have IP connectivity. I know this is basic but, without the configs posted I'm assuming worst case scenario. Once you verified connectivity, use the network statements 192.1.1.0 0.0.0.255 area 0 if that is the IP subnet of the serial interfaces. You may also want to configure loopback interfaces for the neighbor ID.

See this link for a step-by-step walkthrough.

http://www.cisco.com/en/US/tech/tk365/technologies_configuration_example09186a0080094057.shtml

HTH,

Shaun

Community Member

Re: OSPF configuration

As what Shaun said, first make sure your layer 2 (port & line are up) & 3 (Ping the other IP address) are working.

After verifying that a sample OSPF configuration could be as follows:

ROUTER1

router ospf 1

network 192.1.1.0 0.0.0.255 area 0

network 165.148.120.0 0.0.0.252 area 0

ROUTER2

router ospf 1

network 192.1.2.0 0.0.0.255 area 0

network 165.148.120.0 0.0.0.252 area 0

One other thing to check is the ospf network types are the same.

Tim

Community Member

Re: OSPF configuration

Thanks it worked, my problem was with the serial.

I had configured like this 165.148.120.0 0.0.0.0 area 0 instead of

165.148.120.0 0.0.0.3 area 0.

Thanks good people, you have been a great help.

Community Member

Re: OSPF configuration

Your welcome! Please mark this thread as "solved" and don't forget to rate the responses.

Community Member

Re: OSPF configuration

How do I do that?

211
Views
0
Helpful
12
Replies
CreatePlease to create content