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RE: Doubt on OSPF hub and spoke IEWB 17 4.1 posted 12/21/2005
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Are we sure on that one....I have it set on the config below and everything is
working nicely. I thought that the router-id is not really an IP address
anyway.....
R1......
router ospf 1
 router-id 255.255.255.255
 log-adjacency-changes
 network 172.16.123.0 0.0.0.255 area 0
 neighbor 172.16.123.2
 neighbor 172.16.123.3
!

R1#sh ip ospf nei

Neighbor ID     Pri   State           Dead Time   Address         Interface
2.2.2.2           0   FULL/DROTHER    00:01:34    172.16.123.2
Serial0/0.123
172.16.30.3       0   FULL/DROTHER    00:01:53    172.16.123.3
Serial0/0.123
R1#

at the remotes.....

R2#sh ip ospf nei

Neighbor ID     Pri   State           Dead Time   Address         Interface
255.255.255.255   1   FULL/DR         00:01:40    172.16.123.1    Serial0
R2#

Any reason why this works with the router-id of 255.255.255.255?

Dave

-----Original Message-----
From: Scott Morris
To: Schulz, Dave; nobody@xxxxxxxxxxxxxx; ''Gustavo  Novais' '; ''James
Matrisciano' '; ''Cisco  certification  ' '
Sent: 12/21/2005 8:48 PM
Subject: RE: Doubt on OSPF hub and spoke IEWB 17 4.1

You can't set at:

255.255.255.255
0.0.0.0
0.0.0.1

Other than those you should be fine.

Scott

-----Original Message-----
From: nobody@xxxxxxxxxxxxxx [mailto:nobody@xxxxxxxxxxxxxx] On Behalf Of
Schulz, Dave
Sent: Wednesday, December 21, 2005 6:51 PM
To: Scott Morris ; nobody@xxxxxxxxxxxxxx; 'Gustavo Novais' ; 'James
Matrisciano' ; 'Cisco certification '
Subject: RE: Doubt on OSPF hub and spoke IEWB 17 4.1

I have not seen this lab either, but couldn't we also set the hub
router-id
to the highest value to insure it provide further assurance that it is
the
DR (set at 255.255.255.255)?  Just a thought.

Dave

-----Original Message-----
From: nobody@xxxxxxxxxxxxxx
To: 'Gustavo Novais'; 'James  Matrisciano'; 'Cisco  certification  '
Sent: 12/21/2005 4:51 PM
Subject: RE: Doubt on OSPF hub and spoke IEWB 17 4.1

So why do you NEED to put priority 0 on the spokes?

Put a higher priority on the hub to make sure it'll be the DR.  In a
hub-spoke network, we always want to see the hub as the DR and it makes
life
easier if the spokes are all priority 0 but realistically if the hub is
out
of the picture, nobody can talk to anyone anyway.

Broadcast network type would seem to be the available solution given all
the
things you weren't allowed to do.

Disclaimer:  I haven't seen the lab here at all, so I'm merely reading
parts
of the discussion here!

Scott

-----Original Message-----
From: nobody@xxxxxxxxxxxxxx [mailto:nobody@xxxxxxxxxxxxxx] On Behalf Of
Gustavo Novais
Sent: Wednesday, December 21, 2005 2:01 PM
To: James Matrisciano; Cisco certification
Subject: RE: Doubt on OSPF hub and spoke IEWB 17 4.1

Hi,

Only the fact that you have ip ospf priority 0 on the spokes. Which is
an
interface level command, and breaks the rules.

Other by that you are fine... (but no points for the section :(( )


Gustavo Novais

-----Original Message-----
From: nobody@xxxxxxxxxxxxxx [mailto:nobody@xxxxxxxxxxxxxx] On Behalf Of
James Matrisciano
Sent: quarta-feira, 21 de Dezembro de 2005 18:55
To: Gustavo Novais; Cisco certification
Subject: RE: Doubt on OSPF hub and spoke IEWB 17 4.1

Ok, doing an ip ospf net point-to-multipoint on the hub gets the
nieghbors
to come up, changed the ip ospf priorty on the spokes to 0 and that made
the
hub the DR.  Not seeing routes go across though, wich is a concern....

 So that does not work...

On the hub, I am allowed to change the network type...so I change that
to
broadcast.  I then change the timers on the hub to match hellos @ 30 and
dead at 120...

All works, up and up , neighbors copmplete and I can ping a loop back
interface of one spoke from the other.

Does this break any rules?

-----Original Message-----
From: Gustavo Novais [mailto:gustavo.novais@xxxxxxxxxxx]
Sent: Wednesday, December 21, 2005 1:28 PM
To: James Matrisciano; joshua lauer; Cisco certification
Subject: RE: Doubt on OSPF hub and spoke IEWB 17 4.1

Yep, my gut too.

Just one correction to what you said.

No neighbor command, but only on the spokes you cannot do interface
level
commands.

Gustavo Novais

-----Original Message-----
From: James Matrisciano [mailto:jmatrisciano@xxxxxxxxxxxx]
Sent: quarta-feira, 21 de Dezembro de 2005 18:25
To: Gustavo Novais; joshua lauer; Cisco certification
Subject: RE: Doubt on OSPF hub and spoke IEWB 17 4.1

Sounds like a tunnel to me, but without labbing it up and testing it,
can
not say.  I am in the middle of labbing something else up and will see
if I
can throw some opsf over the frame and get it to work with the
restrictions
you are saying...

Hub is MP interface
Spokes are Physical

No Neighbor No ip ospf network commands

I will let you know if I come up with anything, but my gut is saying
tunnel

-----Original Message-----
From: nobody@xxxxxxxxxxxxxx [mailto:nobody@xxxxxxxxxxxxxx] On Behalf Of
Gustavo Novais
Sent: Wednesday, December 21, 2005 1:17 PM
To: joshua lauer; Cisco certification
Subject: RE: Doubt on OSPF hub and spoke IEWB 17 4.1

Hello

The issue is that they are not allowing me to change anything at
interface
level on the spokes. So, to change from NBMA to p2MP(-NB) I would need
to do
that. (I will not try P2MP-NB, because you need to specify neighbors,
which
I can't)

If you are suggesting to put P2MP on Hub and let spokes on NBMA, I am in
process of trying it.
For what I can see the adjacency is established, but there is no route
exchange.

I'm still at a dead end :(


Thank you for replying

Gustavo Novais

-----Original Message-----
From: joshua lauer [mailto:jslauer@xxxxxxxxxxx]
Sent: quarta-feira, 21 de Dezembro de 2005 18:04
To: Gustavo Novais; Cisco certification
Subject: Re: Doubt on OSPF hub and spoke IEWB 17 4.1

Have you tried point-to-multipoint non-broadcast? See if you establish
adjacency after that...I think the key here is that you are using
physical
interfaces and you cannot adjust anything on the spokes.
PTMP-NB should do the trick unless there's something I'm missing here.

JL


----- Original Message -----
From: "Gustavo Novais" <gustavo.novais@xxxxxxxxxxx>
To: "Cisco certification " <ccielab@xxxxxxxxxxxxxx>
Sent: Wednesday, December 21, 2005 12:52 PM
Subject: Doubt on OSPF hub and spoke IEWB 17 4.1


> Hello
>
>
>
> I'm wondering if and how this exercise is doable.
>
> I'd like to have your opinion.
>
>
>
>
>
> Hub and spoke network. Hub (R5) has a multipoint Serial subinterface.
> Both spokes use their main interface.
>
>
>
> We cannot use any neighbour commands nor any interface level commands
on
> R1 and R2 (spokes).
>
>
>
> We are to configure OSPF on this frame-relay network.
>
>
>
> If we were to configure Non-broadcast network, we would need at least
to
> configure neighbour on hub, and ip ospf priority 0 on the spoke
> interfaces----> failing restrictions.
>
>
>
> If we were to configure any point-to-point or point-to-multipoint
> command that would make us configure network type on the ospf
interface,
> we would fail the restriction.
>
>
>
> If we were to configure broadcast network on hub and change timers on
> hub in order to match the spoke timers... It would not establish
> adjacency, besides the fact that we would have to use neighbour
> commands...
>
>
>
>
>
> Unless I use tunnelling or ppp over FR I really do not see how to
> accomplish this.
>
>
>
> Are there any suggestions?
>
>
>
> Thank you
>
> Gustavo Novais
>
>
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