Frame relay and OSPF Problems under GNS3.

AlexMRAlexMR Member Posts: 275
I am setting up a Lab in GNS3, the topology is a Hub and spoke, with one hub and two spokes connected with a FR switch.

Hub IP address is

I'm really confused because both spokes are getting updates from from each other and remote networks are appearing on both routing tables, but I cant ping any remote interface from the spokes, except than interfaces on the hub.

I couldnt understand the previous paragraph so Im going to try again: I have connectivity from the spokes to the hub. The hub can ping both spokes. The hub is receiving routing updates and sending them to the other spoke. A new network connected and advertised by a spoke is updated on the hub and the other spoke,but when i try to ping that address from the remote spoke, even though the network appears on the routing table, the pings are unsuccessful. I cant even reach one spoke router from the other. All interface are in the same subnet and the neighborgh <ip address> router configuration command has been configured for both spokes on the hub.

It's 4:30Am here and Ive been at this since about 12AM.

Im too's probably something silly and Im really pissed off because ive lost almost 5hours oon this!
Training/Studying for....CCNP (BSCI) and some MS.


  • kalebkspkalebksp Member Posts: 1,033 ■■■■■□□□□□
    My OSPF is getting a little rusty, but if I'm understanding the problem correctly you need "ip ospf network point-to-multipoint" on your hub router under the interface connecting to your frame switch. This tells the hub that the other two routers are not directly connected and it needs to route the traffic between them.
  • AlexMRAlexMR Member Posts: 275
    Thank you Kaleb!! It didnt work when I used it only on the hub but the adjacencies were lost so i remember they had to be configured for the same. Setting all the active OSPF interfaces as point to multipoint did the trick.

    Thanks again.

    Labbing overnight can be counterproductive. Dont you think!?
    Training/Studying for....CCNP (BSCI) and some MS.
Sign In or Register to comment.