OSPF Question

[sadik.bash]

Hello,

I setup both a physical lab and a virtual one using GNS3. I created a simple topology; 3 routers(rt1, rt2, and rt3). RT2 is the hub which has 2 WICs and each WIC is linked to the the other routers(rt1 and rt3). See attached diag. 

I configured OSPF on all routers but when I issue the following command #show ip ospf neighbor at any one of the routers the output comes empty. Also, when I try to ping the rt1 interface from rt2, it fails and vice verse.

Any ideas to fix these issues? 

Here is the ip address configured at each serial intf: 

   rt1:   s0/0/0:  172.16.1.253/30

   rt2:   s0/0/0:  172.16.1.254/30

   rt2:   s0/1/0:  172.16.2.254/30

   rt3:  s0/0/0:   172.16.2.253/30

Here is the part of the config off of rt2: 

interface Loopback2
 ip address 1.1.1.2 255.255.255.0
!         
interface FastEthernet0/0
 description Link to LAN
 ip address 192.168.2.253 255.255.255.0
 duplex auto
 speed auto

!
interface Serial0/0/0
 description link to SK-RTR-01 S0/0
 bandwidth 1536
 ip address 172.16.1.254 255.255.255.252
 no ip redirects
 no ip unreachables
 no ip proxy-arp
 no ip mroute-cache
!
interface Serial0/1/0
 description link to SK-RTR-03 S0/0
 bandwidth 1536
 ip address 172.16.2.254 255.255.255.252
 no ip redirects
 no ip unreachables
 no ip proxy-arp
 no ip mroute-cache
!
router ospf 10
 log-adjacency-changes
 network 172.16.1.0 0.0.0.3 area 0
 network 172.16.2.0 0.0.0.3 area 0

Best, zK 

[Vkatouzian1]

Hi , i can't see router-id for your routers , in ospf protocol , first you need to define a router id .

[Vkatouzian1]

Hi , i can't see router-id for your routers , in ospf protocol , first you need to define a router id . Also your network address is wrong . It suppose to be 172.16.1.252 and 172.16.2.252 with wild mask 0.0.0.3

[Ruben Cocheno]

the router-id is get automatically from loopbacks/interface IPs. Serial interfaces using HDLC, you can change it for encapsulation PPP and apply a clock-rate (DCE-DTE)

you need to amend the network statements in OSPF for:

router ospf 10
 log-adjacency-changes
 network 172.16.1.252 0.0.0.3 area 0
 network 172.16.2.252 0.0.0.3 area 0