ospf netmask mismatch

[Martin Kraus]

On Mon, Jul 12, 2010 at 03:53:31PM +0200, Ondrej Zajicek wrote:
> On Mon, Jul 12, 2010 at 01:39:25PM +0200, Martin Kraus wrote:
> The private /25 prefixes uses private IP addresses? There was a change in BIRD
> that interface with more IP addresses works like more virtual interfaces with
> regard to OSPF, but it should not cause problems and it was earlier change
> (~ 1.2.0).

I have 1.1.4 in most of the network.

> 
> It is strange that reported netmask is /31, but you said that it uses
> 212.71.191.77/30 . Could you send me output of 'show ospf interface'?

When I get rid of the private prefixes it all works fine. when I add them it
gets  the netmask mismatch (255.255.255.128) again. the /25 is set on the private
prefixes.

birdc> s o n

Interface eth1 (212.71.191.76/30)
    Type: nbma (strict)
    Area: 0.0.0.0 (0)
    State: dr 
    Priority: 1
    Cost: 30
    Hello timer: 10
    Poll timer: 10
    Wait timer: 10
    Dead timer: 30
    Retransmit timer: 5
    Designed router (ID): 212.71.177.118
    Designed router (IP): 212.71.191.77
    Backup designed router (ID): 212.71.152.98
    Backup designed router (IP): 212.71.191.78
Interface eth1 (172.23.5.128/25)
    Type: nbma (strict)
    Area: 0.0.0.0 (0)
    State: dr 
    Priority: 1
    Cost: 30
    Hello timer: 10
    Poll timer: 10
    Wait timer: 10
    Dead timer: 30
    Retransmit timer: 5
    Designed router (ID): 212.71.177.118
    Designed router (IP): 172.23.5.129
    Backup designed router (ID): 0.0.0.0
    Backup designed router (IP): 0.0.0.0

when I set 172.23.5.254/26 on the interface as another ip address, the error
changes to:

Bad HELLO packet from 212.71.191.78 - netmask mismatch (255.255.255.192)

from that I'd asume that somehow the netmask is taken from the wrong network
address.

mk