Re: OSPF Virtual Links and PPPoFR

Can you ping R1's loopback from R2 and R3? It may be a reachability problem
with PPPoFR in a hub and spoke topology. I have seen certain instances where
the hub brings up multiple virtual-access interfaces but it sends packets
down the wrong one.

Example, the following output is from a Hub, R2. 10.1.1.1 is a loopback on
R1:

O IA 10.1.1.1 [110/2] via 172.16.0.1, 00:00:06, Virtual-Access3

However the, the virtual-access3 interface is bound to the DLCI headed
towards R3. The virtual-access interface is created dynamically.

R2#sho ip osp ne

Neighbor ID Pri State Dead Time Address Interface
10.1.1.3 0 FULL/ - 00:01:39 172.16.0.3
Virtual-Access3
10.1.1.1 0 FULL/ - 00:01:39 172.16.0.1
Virtual-Access2

R2 cannot reach R1 and virtual-links will not come up because of this. I
think the root of the problem is having two interfaces (virtual-acess
interfaces in this case) with one IP address. You can try to remove pieces
of your configuration and add them back, you can try multiple templates
(with the same IP), or even try changing network types, but the chances of
this happening seem to be pretty good.

I found this blog entry, but I am not sure ip unnumbered will help in your
case, may be worth a shot. I was not able to get it to work.

http://cciepursuit.wordpress.com/2008/09/21/ios-error-with-ospf-point-to-multipoint-network-in-pppofr-hub-and-spoke-topology/

On Wed, Jul 15, 2009 at 5:56 PM, Victor <cisco.all.stuff_at_gmail.com> wrote:

> I have 3 routers 1,2 and 3... where 2 is the hub, all of them are ABRs
> sharing the area 77 and have other area configured in theirs Loopback
> interfaces. Router 1 has a Lo with Area 0, Router 2 has a Lo with Area 2
> and
> Router 3 has a Lo with Area 3. So I'm trying to connect the Areas 2 and 3
> to
> Area 0 through Area 77 ( area 77 virtual-link Router1-ID and viceversa)
>
> I hope now is clearer.
>
> Thanks and Brgds..... Victor
>
> On 7/15/09, Joe Astorino <jastorino_at_ipexpert.com> wrote:
> >
> > What do your areas look like?
> >
> > - what is the area between hub and spoke 1
>
>
> - what is the area between hub and spoke 2
>
> - Do you have any other areas configured for something like loopbacks?
>
>
> On Wed, Jul 15, 2009 at 6:09 PM, Victor <cisco.all.stuff_at_gmail.com>
> wrote:
> >
> >> Understand.... the initial config is with the default interface type
> >> (point-to-point for PPPoFR) in this case I can't have the VL up between
> the
> >> hub and one spoke (spoke has the area 0) but I can have up the VL
> between
> >> both spokes. After changing the config (interfaces ospf type point to
> >> multipoint) both VL come up. My question is: if the interfaces type in
> the
> >> first case are equal / compatible, why the VL does not come up between
> >> hub-spoke?? I think it may be simple but I'm missing it.
> >>
> >> Thanks & Brgds..... Victor.
> >>
> >> On 7/15/09, Joe Astorino <jastorino_at_ipexpert.com> wrote:
> >>>
> >>> I'm confused about your question now -- Can you please re-word that?
> >>> What was the "original configuration" and what is the configuration
> now? In
> >>> general, the OSPF network types should match. You can get away with
> >>> mismatches in some cases by tweaking timers, but I wouldn't recommend
> it
> >>> unless you need to for a task.
> >>>
> >>> On Wed, Jul 15, 2009 at 4:48 PM, Victor <cisco.all.stuff_at_gmail.com
> >wrote:
> >>>
> >>>> Sorry...... a clarification when I said: "by default the ospf network
> >>>> type for FR multipoint subinterfaces is multipoint non_broadcast"....
> I
> >>>> really meant non_broadcast..... by mistake I repeated multipoint.
> >>>>
> >>>> Brgds.......Victor.
> >>>>
> >>>>
> >>>> On 7/15/09, Victor <cisco.all.stuff_at_gmail.com> wrote:
> >>>>>
> >>>>> Thank you very much Brian and Joe,
> >>>>>
> >>>>> That was the point...... now I have this working, I changed the
> network
> >>>>> type to point-to-multipoint, however I couldn't understand well
> what's
> >>>>> happening. Well....by default the ospf network type for FR multipoint
> >>>>> subinterfaces is multipoint non_broadcast and the ospf network type
> when
> >>>>> using PPPoFR is poin-to-point (Virtual Access) but all the interfaces
> have
> >>>>> the same network type, should not they work??
> >>>>>
> >>>>> So, with the initial config they became neighbors but the Virtual
> Link
> >>>>> do not comes up, after I changed to p-t-m it's working
> >>>>>
> >>>>> Sorry if I'm asking and stupidity but I've been searching on the
> Cisco
> >>>>> docs and I didn't find much information about these details.
> >>>>>
> >>>>> Could you pls add some other information on this issue?? Thanks again
> >>>>> for your help
> >>>>>
> >>>>>
> >>>>> Cheers.... Victor.
> >>>>>
> >>>>> On 7/15/09, Brian Dennis <bdennis_at_internetworkexpert.com> wrote:
> >>>>>>
> >>>>>> Victor,
> >>>>>> Did you check to see what the OSPF network type is on the hub's
> >>>>>> interface when using standard FR and then when using PPPoFR?
> >>>>>>
> >>>>>> Brian Dennis, CCIEx5 #2210 (R&S/ISP-Dial/Security/SP/Voice)
> >>>>>> bdennis_at_internetworkexpert.com
> >>>>>>
> >>>>>> Internetwork Expert, Inc.
> >>>>>> http://www.InternetworkExpert.com<
> http://www.internetworkexpert.com/>
> >>>>>> Toll Free: 877-224-8987 x 703
> >>>>>> Outside US: 775-826-4344 x 703
> >>>>>>
> >>>>>> ----- Original Message -----
> >>>>>> From: "Victor" <cisco.all.stuff_at_gmail.com>
> >>>>>> Sent: Tue, July 14, 2009 19:39
> >>>>>> Subject:OSPF Virtual Links and PPPoFR
> >>>>>>
> >>>>>>
> >>>>>> Hello Guys,
> >>>>>> I've been trying to get running OSPF Virtual Links over a 3 routers
> >>>>>> topology
> >>>>>> 1 hub + 2 spokes using PPPoFR for connecting between them, where one
> >>>>>> of the
> >>>>>> spokes is the backbone and I have some Loopbacks created on each
> >>>>>> router on
> >>>>>> different areas, so finally I only can get running the Virtual Link
> >>>>>> going
> >>>>>> from spoke to spoke but NEVER the VL between the hub to the spoke
> >>>>>> (area 0).
> >>>>>> I changed the PPPoFR config and used only FR and everything works
> OK,
> >>>>>> when I
> >>>>>> try to use PPPoFR (no changes in OSPF config) I get the same
> problem.
> >>>>>>
> >>>>>> I'm sure I'm missing something..... do you have any suggestion??
> >>>>>>
> >>>>>> Regards.... Victor.
> >>>>>>
> >>>>>>
> >>>>>> Blogs and organic groups at http://www.ccie.net
> >>>>>>
> >>>>>>
> >>>>>>
> _______________________________________________________________________
> >>>>>> Subscription information may be found at:
> >>>>>> http://www.groupstudy.com/list/CCIELab.html
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>> ----- End of original message -----
> >>>>>>
> >>>>>>
> >>>>>
> >>>>
> >>>>
> >>>
> >>>
> >>>
> >>> --
> >>> Regards,
> >>>
> >>> Joe Astorino - CCIE #24347 R&S
> >>> Technical Instructor - IPexpert, Inc.
> >>> Cell: +1.586.212.6107
> >>> Fax: +1.810.454.0130
> >>> Mailto: jastorino_at_ipexpert.com
> >>>
> >>
> >>
> >>
> >
> >
> >
> > --
> > Regards,
> >
> > Joe Astorino - CCIE #24347 R&S
> > Technical Instructor - IPexpert, Inc.
> > Cell: +1.586.212.6107
> > Fax: +1.810.454.0130
> > Mailto: jastorino_at_ipexpert.com
>
>
> Blogs and organic groups at http://www.ccie.net
>
> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
>
>
>
>
>
>
>
>

-- 
Bryan Bartik
CCIE #23707 (R&S), CCNP
Sr. Support Engineer - IPexpert, Inc.
URL: http://www.IPexpert.com
Blogs and organic groups at http://www.ccie.net