ospf hello's are not received on one side

[Haris P]

Dears ,

I'm trying to run OSPF between two of my routers conected via 2 switches . The IP address on both sides are configured as in dot1Q sub-interface . I did debug for both of my routers ..and i saw that one side of the link hellos are not receiving . I put the network type to non broadcast and the ospf relationship was established...any clues for this situation

Ruter1(Area3: 172.16.42.10)-trunk---2950-..............-(vlan 103)--................-2960---trunk-----Rouer2(area3:172.16.42.1)

the IP's on both sides are configured as

interface GigabitEthernet0/2.10
encapsulation dot1Q 10
ip address 172.16.42.1 255.255.255.224

Hellos are send and received

Feb 28 16:26:00.534: OSPF: End of hello processing
Feb 28 16:26:30.494: OSPF: Send hello to 224.0.0.5 area 3 on FastEthernet6/0.10 from 172.16.42.10
Feb 28 16:26:30.534: OSPF: Rcv hello from 172.16.42.254 area 3 from FastEthernet6/0.10 172.16.42.1
Feb 28 16:26:30.534: OSPF: End of hello processing
Feb 28 16:27:00.495: OSPF: Send hello to 224.0.0.5 area 3 on FastEthernet6/0.10 from 172.16.42.10
Feb 28 16:27:00.531: OSPF: Rcv hello from 172.16.42.254 area 3 from FastEthernet 6/0.10 172.16.42.1
Feb 28 16:27:00.531: OSPF: End of hello processing
Feb 28 16:27:30.495: OSPF: Send hello to 224.0.0.5 area 3 on FastEthernet6/0.10 from 172.16.42.10

Logs from R2 ( Hellos are send ,but not received from R1)

Mar  1 05:37:01.267: OSPF: Send hello to 224.0.0.5 area 3 on GigabitEthernet0/2.10 from 172.16.42.1
Mar  1 05:37:31.267: OSPF: Send hello to 224.0.0.5 area 3 on GigabitEthernet0/2.10 from 172.16.42.1
Mar  1 05:38:01.267: OSPF: Send hello to 224.0.0.5 area 3 on GigabitEthernet0/2.10 from 172.16.42.1
Mar  1 05:38:31.267: OSPF: Send hello to 224.0.0.5 area 3 on GigabitEthernet0/2.10 from 172.16.42.1
Mar  1 05:39:01.267: OSPF: Send hello to 224.0.0.5 area 3 on GigabitEthernet0/2.10 from 172.16.42.1
Mar  1 05:39:31.268: OSPF: Send hello to 224.0.0.5 area 3 on GigabitEthernet0/2.10 from 172.16.42.1
Mar  1 05:40:01.268: OSPF: Send hello to 224.0.0.5 area 3 on GigabitEthernet0/2.10 from 172.16.42.1
Mar  1 05:40:31.268: OSPF: Send hello to 224.0.0.5 area 3 on GigabitEthernet0/2.10 from 172.16.42.1
Mar  1 05:41:01.268: OSPF: Send hello to 224.0.0.5 area 3 on GigabitEthernet0/2.10 from 172.16.42.1
Mar  1 05:41:31.268: OSPF: Send hello to 224.0.0.5 area 3 on GigabitEthernet0/2.10 from 172.16.42.1

regards

[lgijssel]

Check ip connectivity between the routers.

Check the switches for filters (access-lists) blocking multicast traffic.

regards,

Leo

[Haris P]

Dear Leo,

I dont have any filters or ACL to block multicast traffic . Moreover its blocking one side only . On R1 hellos are receiving , but on R2 it is not . I suspect the problem with 2950 switch

[cadet alain]

Can you  post config of 2 switches and  also do a debug ip ospf hello on each router.

Also on each router : access-list 180 permit ospf any any

                               debug ip packet 180

Regards.

Alain.

[lgijssel]

I dont have any filters or ACL to block multicast traffic . Moreover its blocking one side only . On R1 hellos are receiving , but on R2 it is not . I suspect the problem with 2950 switch

That's why I said you should first verify ip connectivity.

If its a hardware problem, you can only find it when the config is known to be OK.

Perhaps you can try to plug the router into a different port on the switch?

regards,

Leo

[Haris P]

On Switch connected to R1

interface FastEthernet0/24
description Router(R1)

switchport mode trunk
switchport priority extend trust
duplex full
spanning-tree portfast

interface FastEthernet0/23
switchport access vlan 10
switchport mode access

the cable from port 0/23 is going to other switch and it is also having same config

[c.doelhoffs]

Hi,

You may have an issue with the Multicast management in the switch. I suggest to check the IGMP configuration of the switch.

Regards,

Christian