[nsp] OSPF over RBE - no full adjacency

[Stephen J. Wilcox]

On Wed, 21 Jan 2004, Vincent De Keyzer wrote:

> Ok, I had two problems: MTU (had to change it to 1500 in order to get
> full adjacency) and network-type (had to change it to remove discrepancy
> in the OSPF DB and get the OSPF routes into the routing table).
> 
> So now RouterA looks like this:
> 
> interface ATM2/0.12801 point-to-point
>  description To Router B 
>  ip address x.y.240.81 255.255.255.252
>  ip verify unicast reverse-path
>  ip mtu 1500
>  ip ospf network broadcast
>  atm route-bridged ip
>  pvc miguel 12/801
>   vbr-nrt 2000 2000
>   encapsulation aal5snap
>  !
>  ntp broadcast
> end
> 
> Now two questions are left:
> 1) What is the difference between "mtu 1500" and "ip mtu 1500"?
are they different?

> 2) I had to change the ATM side to "broadcast". Could I also have
> changed Ethernet side to "Point-to-point"?

I dont think you can do that, you could have it non broadcast and specify 
neighbors tho, the point is to have both sides configured the same (bearing in 
mind they default differently) and to have the media support what you configure 
(eg broadcast wont work in a point to multipoint scenario)

Steve

> 
> Vincent
> 
> 
> 
> > -----Original Message-----
> > From: jgh_cisco [mailto:jgh_cisco at idcomnet.no] 
> > Sent: mercredi 21 janvier 2004 21:24
> > To: 'Vincent De Keyzer'; cisco-nsp at puck.nether.net
> > Subject: SV: [nsp] OSPF over RBE - no full adjacency
> > 
> > 
> > Hello !
> > 
> > You have an IP MTU issue.
> > OSPF checks the MTU before building the adjacency.
> > ATM defaults to 4470 bytes, and Ethernet 1500.
> > 
> > Try adding "ip mtu 1500" under your ATM subinterface.
> > 
> > You should get a descriptive debug message if you do "debug 
> > ip ospf adj"
> > 
> > Jan G. Hope
> > 
> > > Hello people,
> > > 
> > > how do I make the following two boxes establish an OSPF adjacency?
> > > 
> > > It seems that simple network statements are not enough - neighbors 
> > > remain in Exstart/Exchange phase.
> > > 
> > > Vincent
> > > 
> > > 
> > > Router A:
> > > 
> > > interface ATM2/0.12801 point-to-point
> > > 
> > > Router B:
> > > 
> > > interface Ethernet0/0
> > 
> > 
> 
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