[c-nsp] OSPF excessive retransmissions

[Karol Mares]

Hi,

On 9/11/07, Karol Mares <karol.mares at gmail.com> wrote:
>
>
>
> On 9/11/07, Mark Pace Balzan <mpb at melitacable.com> wrote:
> >
> > Hi,
> >
> >
> > I have a number of cisco and non-cisco OSPF speakers on an ethernet lan
> > that have been working ok for a while.
> >
> > I changed switch and added a new router (new boxes are cisco kit), and
> > Im getting the following between some neighbours and the new box:
> >
> > 000799: Sep 11 07:26:14.252 CET: OSPF: Killing nbr 192.168.0.33 on
> > GigabitEthernet2/39 due to excessive (25) retransmissions
> > 000800: Sep 11 07:26:14.252 CET: OSPF: 192.168.0.33 address 192.168.1.67
> > on GigabitEthernet2/39 is dead, state DOWN
> > 000801: Sep 11 07:26:14.252 CET: %OSPF-5-ADJCHG: Process 100, Nbr
> > 192.168.0.33 on GigabitEthernet2/39 from FULL to DOWN, Neighbor Down:
> > Too many retransmissions
> >
> >
> > Anyone has any clue what the cause for OSPF re-transmissions is, and any
> > pointers to some explanations to understand whats happening - my search
> > on CCO was rather futile unfortunately.
> >
> >
> > Thanks
> >
> > Mark
>
>
>
> Check out the MTU and physical counter parameters on  interfaces
> connecting OSPF neighbours - most likely causing this behaviour
>
> --
>            iso
>


You can check also in your OSPF database , if the LSA is not cycling around,
if you have any kind of loop in your network.