Re: Multicast over NBMA makes my brain hurt

Keller,

I believe the behavior you're seeing is R2 *trying* to build the SPT (that
is why the first ping comes through ). This is due to the strange behavior
in IOS where switching to the SPT fails when the RPT and SPT paths point to
the same DLCI on a multipoint interface.

There are two ways to solve this:

Set 'ip pim spt-threshold infinity' on R2, so it never tries to switch to
the SPT.
or
Make the frame-relay interface on R2 a point-to-point sub-interface

-Yuri

On Mon, Nov 12, 2012 at 4:20 AM, Baldwin, Patrick A. (MSFC-EO60)[HOSC
SERVICES CONTRACT] <alex.baldwin_at_nasa.gov> wrote:

> You need ip pim sparse on l0 of r1
>
> Sent from my iPad
>
> On Nov 12, 2012, at 5:31 AM, "Keller Giacomarro" <keller.g_at_gmail.com>
> wrote:
>
> > For your full review, if you like...
> > R1: http://pastebin.com/raw.php?i=cHFzBDEh
> > R2: http://pastebin.com/raw.php?i=Dn6ATSPM
> > R3: http://pastebin.com/raw.php?i=yEwnnc8y
> > GNS3: http://pastebin.com/raw.php?i=A4MnALTq
> >
> > Configs and GNS3 are written for IOS 15.1. I have also tried this in
> 12.4
> > with identical results.
> >
> > Note that I did this in GNS3 after I experienced the problem with my real
> > equipment, so I do not believe this is a GNS3 problem.
> >
> > Thoughts appreciated!
> >
> > Keller Giacomarro
> > keller.g_at_gmail.com
> >
> >
> > On Mon, Nov 12, 2012 at 4:47 AM, Keller Giacomarro <keller.g_at_gmail.com
> >wrote:
> >
> >> Yep, set to dr-priority 1000 in my configs.
> >>
> >> R1#show ip pim int
> >>
> >> Address Interface Ver/ Nbr Query DR DR
> >> Mode Count Intvl Prior
> >> 1.1.1.1 Loopback0 v2/S 0 30 1
> >> 1.1.1.1
> >> 10.0.0.1 Serial1/0 v2/S 0 30 1000
> >> 10.0.0.1
> >> R1#
> >>
> >>
> >> Keller Giacomarro
> >> keller.g_at_gmail.com
> >>
> >>
> >>
> >> On Mon, Nov 12, 2012 at 4:38 AM, oo IPX <oispxl_at_gmail.com> wrote:
> >>
> >>> have you tried making the R1 DR,
> >>>
> >>> R3(config)#do ping 224.1.1.1 rep 100
> >>>
> >>> Type escape sequence to abort.
> >>> Sending 100, 100-byte ICMP Echos to 224.1.1.1, timeout is 2 seconds:
> >>> ......
> >>> Reply to request 6 from 10.1.123.2, 84 ms
> >>> Reply to request 7 from 10.1.123.2, 104 ms
> >>> Reply to request 8 from 10.1.123.2, 76 ms
> >>> Reply to request 9 from 10.1.123.2, 56 ms
> >>> Reply to request 10 from 10.1.123.2, 76 ms
> >>> Reply to request 11 from 10.1.123.2, 56
> >>>
> >>>
> >>>
> >>> those loss of pings is because i cleared the mroute table.
> >>>
> >>>
> >>> R3(config)#do sh ip pim inter s0/0 de | I DR
> >>> PIM DR: 10.1.123.1
> >>> R3(config)#
> >>>
> >>> R2(config)#do sh ip pim inter s0/0 de | I DR
> >>> PIM DR: 10.1.123.1
> >>> R2(config)#
> >>>
> >>> R1(config-if)#do sh run inter s0/0
> >>> Building configuration...
> >>>
> >>> Current configuration : 374 bytes
> >>> !
> >>> interface Serial0/0
> >>> ip address 10.1.123.1 255.255.255.0
> >>> ip pim dr-priority 90
> >>> ip pim nbma-mode
> >>> ip pim sparse-mode
> >>> encapsulation frame-relay
> >>> no ip split-horizon eigrp 1
> >>> no ip mroute-cache
> >>> clock rate 2000000
> >>> frame-relay map ip 10.1.123.1 111
> >>> frame-relay map ip 10.1.123.2 111 broadcast
> >>> frame-relay map ip 10.1.123.3 101 broadcast
> >>> no frame-relay inverse-arp
> >>> end
> >>>
> >>>
> >>> On Mon, Nov 12, 2012 at 2:32 PM, Keller Giacomarro <keller.g_at_gmail.com
> >wrote:
> >>>
> >>>> Okay, I must be totally missing the boat here, but I can't get
> Multicast
> >>>> over NBMA to work AT ALL.
> >>>>
> >>>> R2-----\
> >>>> -------- R1
> >>>> R3-----/
> >>>>
> >>>> All interfaces are physical interfaces with static ipv4 mappings. R1
> has
> >>>> DLCIs to both spoke routers, and spoke routers only have DLCIs to R1.
> >>>> This
> >>>> is as simple as I know how to get it.
> >>>>
> >>>> *** R1 ***
> >>>> interface Serial1/0
> >>>> ip address 10.0.0.1 255.255.255.0
> >>>> ip pim dr-priority 1000
> >>>> ip pim nbma-mode
> >>>> ip pim sparse-mode
> >>>> encapsulation frame-relay
> >>>> frame-relay map ip 10.0.0.3 103 broadcast
> >>>> frame-relay map ip 10.0.0.2 102 broadcast
> >>>> no frame-relay inverse-arp
> >>>> !
> >>>> interface Loopback0
> >>>> ip address 1.1.1.1 255.255.255.0
> >>>> !
> >>>> ip pim rp-address 1.1.1.1
> >>>>
> >>>> *** R2 ***
> >>>> interface Serial1/0
> >>>> ip address 10.0.0.2 255.255.255.0
> >>>> ip pim sparse-mode
> >>>> encapsulation frame-relay
> >>>> frame-relay map ip 10.0.0.3 201
> >>>> frame-relay map ip 10.0.0.1 201 broadcast
> >>>> !
> >>>> interface Loopback0
> >>>> ip address 2.2.2.2 255.255.255.255
> >>>> ip pim sparse-mode
> >>>> ip igmp join-group 229.0.0.2
> >>>> !
> >>>> ip route 1.1.1.1 255.255.255.255 10.0.0.1
> >>>> ip pim rp-address 1.1.1.1
> >>>>
> >>>> *** R3 ***
> >>>> interface Serial1/0
> >>>> ip address 10.0.0.3 255.255.255.0
> >>>> ip pim sparse-mode
> >>>> encapsulation frame-relay
> >>>> frame-relay map ip 10.0.0.2 301
> >>>> frame-relay map ip 10.0.0.1 301 broadcast
> >>>> !
> >>>> ip route 1.1.1.1 255.255.255.255 10.0.0.1
> >>>> ip pim rp-address 1.1.1.1
> >>>>
> >>>> *** Testing ***
> >>>> Ping is from R3 to 229.0.0.2, which is joined on R2. The first ping
> goes
> >>>> through fine, all others drop until the mroute times out on R1.
> >>>>
> >>>> ---
> >>>> R3(config)#do ping 229.0.0.2 re 10
> >>>> Type escape sequence to abort.
> >>>> Sending 10, 100-byte ICMP Echos to 229.0.0.2, timeout is 2 seconds:
> >>>>
> >>>> Reply to request 0 from 2.2.2.2, 48 ms.........
> >>>> R3(config)#
> >>>> ---
> >>>>
> >>>> Debugs indicate that R2 (subscriber router) is sending a PIM Prune to
> R1
> >>>> (the hub/RP) as soon as the first packet is received. R2 retains the
> >>>> (S,G)
> >>>> mapping with an incoming interface of s1/0, but the prune message
> causes
> >>>> R1
> >>>> to remove S1/0 from the OIL. Any packets after the first are dropped
> on
> >>>> R1
> >>>> due to the olist being null.
> >>>>
> >>>> I don't understand why the PIM Prune is being generated on R2 for R1
> --
> >>>> isn't that the router that's sending the stream? Most of all, I don't
> >>>> understand why something that seems so simple isn't working!
> >>>>
> >>>> In conclusion, I hate multicast!
> >>>>
> >>>> Appreciate any help you might be able to provide. =)
> >>>>
> >>>> Keller Giacomarro
> >>>> keller.g_at_gmail.com
> >>>>
> >>>>
> >>>> Blogs and organic groups at http://www.ccie.net
> >>>>
> >>>>
> _______________________________________________________________________
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Received on Mon Nov 12 2012 - 09:38:58 ART