Re: Multicast issue in NBMA

Thanks Brian for this: *"and since you can't route link-local multicast"*...All
my assumption was both spokes are in the same broadcast domain(and I have
the "broadcast" keyword with the frame map command) even with the each
spoke having a next-hop as the other spoke...That was the concept/fact I
was forgetting....And yes,using a point-to-multipoint does work as well as
the Tunnel as suggested by Tony.

Thanks everone.

On Thu, Jul 4, 2013 at 8:58 PM, Brian McGahan <bmcgahan_at_ine.com> wrote:

> The issue is like you said, the join for the RPF neighbor is for someone
> who can't be reached by the spoke. Even though the PIM join is a
> multicast, there is an encoded unicast address in the JOIN packet. The
> result is that the hub will drop the packet since it's not the destination
> and since you can't route link-local multicast. The solution for this is
> to change to OSPF point-to-multipoint where the hub will be the next-hop,
> and hence the encoded unicast address in the multicast join will be the
> connected neighbor, or like Tony said to use a GRE tunnel.
>
> In reality both of these solutions are a hack. The correct design
> solution is to only use p2p IP subnets and p2p subinterfaces for NBMA,
> which remove tons of design problems such as this with multicast. Of
> course within the scope of the CCIE lab exam you have to deal with their
> restrictions. So theoretically if they were to say that you have to use
> OSPF broadcast network type and you can't use P2P subinterfaces and the
> sender and receiver are on different spokes then you'd have to tunnel the
> traffic. If the sender/receiver is behind the hub and the sender/receiver
> is behind the spoke then it's fine, it's only a spoke to spoke issue.
>
>
> HTH,
>
> Brian McGahan, CCIE #8593 (R&S/SP/Security), CCDE #2013::13
> bmcgahan_at_INE.com
>
> Internetwork Expert, Inc.
> http://www.INE.com
>
>
> -----Original Message-----
> From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of
> Taio Bone
> Sent: Thursday, July 04, 2013 2:52 PM
> To: Tony Singh
> Cc: Cisco certification
> Subject: Re: Multicast issue in NBMA
>
> Also ALL routers are 7200 series
>
> R2(config)#do sh ver
> Cisco IOS Software, 7200 Software (C7200-IK9O3S-M), Version 12.4(12c),
> RELEASE SOFTWARE (fc1) Technical Support: http://www.cisco.com/techsupportCopyright (c) 1986-2007 by Cisco Systems, Inc.
> Compiled Fri 13-Jul-07 09:55 by prod_rel_team
>
>
>
> On Thu, Jul 4, 2013 at 8:49 PM, Taio Bone <taiobtnh_at_gmail.com> wrote:
>
> > R1
> >
> > FRS
> >
> > R2 R3
> > f0/0 f0/0
> > | |
> > | |
> > f0/0 f0/0
> > R4 R5
> > *
> > *
> > **R3 is the RP and are statically configure on ALL routers including
> > the RP itself*
> >
> > **Igmp join is being sent from R4's f0/0 interface....R2 receives the
> > join message and has the (*,G) entry for the group*
> >
> > R2(config)#
> > PIM(0): Check RP 3.3.3.3 into the (*, 224.6.6.6) entry
> > PIM(0): Received v2 Join/Prune on FastEthernet0/0 from 24.24.24.4, to
> > us
> > PIM(0): Join-list: (*, 224.6.6.6), RPT-bit set, WC-bit set, S-bit set
> > PIM(0): Add FastEthernet0/0/24.24.24.4 to (*, 224.6.6.6), Forward
> > state, by PIM *G Join
> > PIM(0): Building Triggered (*,G) Join / (S,G,RP-bit) Prune message for
> > 224.6.6.6
> > R2(config)#
> >
> > R2(config)#do sh ip mroute 224.6.6.6
> > IP Multicast Routing Table
> > Flags: D - Dense, S - Sparse, B - Bidir Group, s - SSM Group, C -
> > Connected,
> > L - Local, P - Pruned, R - RP-bit set, F - Register flag,
> > T - SPT-bit set, J - Join SPT, M - MSDP created entry,
> > X - Proxy Join Timer Running, A - Candidate for MSDP
> Advertisement,
> > U - URD, I - Received Source Specific Host Report,
> > Z - Multicast Tunnel, z - MDT-data group sender,
> > Y - Joined MDT-data group, y - Sending to MDT-data group
> > Outgoing interface flags: H - Hardware switched, A - Assert winner
> > Timers: Uptime/Expires
> > Interface state: Interface, Next-Hop or VCD, State/Mode
> >
> > (*, 224.6.6.6), 00:01:11/00:03:16, RP 3.3.3.3, flags: SJC
> > Incoming interface: Serial1/0, RPF nbr 10.10.10.3
> > Outgoing interface list:
> > FastEthernet0/0, Forward/Sparse, 00:01:11/00:03:16
> >
> >
> > *
> > *
> > **the multicast source is being sent from R5's f0/0 interface,hence
> > the DR is R3 which happens to be the RP as well as evident by the
> > below output
> > *
> >
> >
> > R3(config)#do sh log
> > Syslog logging: enabled (12 messages dropped, 1 messages rate-limited,
> > 0 flushes, 0 overruns, xml disabled, filtering disabled)
> > Console logging: level alerts, 150 messages logged, xml disabled,
> > filtering disabled
> > Monitor logging: level debugging, 0 messages logged, xml disabled,
> > filtering disabled
> > Buffer logging: level debugging, 165 messages logged, xml disabled,
> > filtering disabled
> > Logging Exception size (8192 bytes)
> > Count and timestamp logging messages: disabled
> >
> > No active filter modules.
> >
> > Trap logging: level informational, 62 message lines logged
> >
> > Log Buffer (8192 bytes):
> >
> > PIM(0): Received v2 Join/Prune on FastEthernet0/0 from 35.35.35.5, to
> > us
> > PIM(0): Join-list: (*, 224.0.1.40), RPT-bit set, WC-bit set, S-bit set
> > PIM(0): Update FastEthernet0/0/35.35.35.5 to (*, 224.0.1.40), Forward
> > state, by PIM *G Join
> > PIM(0): v1, bad checksum from 35.35.35.5 (FastEthernet0/0)
> > PIM(0): Check RP 3.3.3.3 into the (*, 224.2.2.2) entry
> > PIM(0): Received v2 Register on FastEthernet0/0 from 35.35.35.5
> > for 35.35.35.5, group 224.2.2.2
> > PIM(0): Send v2 Register-Stop to 35.35.35.5 for 35.35.35.5, group
> > 224.2.2.2
> > PIM(0): Received v2 Register on FastEthernet0/0 from 35.35.35.5
> > for 5.5.5.5, group 224.2.2.2
> > PIM(0): Send v2 Register-Stop to 35.35.35.5 for 5.5.5.5, group
> > 224.2.2.2
> > PIM(0): v1, bad checksum from 35.35.35.5 (FastEthernet0/0)
> > PIM(0): Building Periodic (*,G) Join / (S,G,RP-bit) Prune message for
> > 224.0.1.40
> > PIM(0): Building Periodic (*,G) Join / (S,G,RP-bit) Prune message for
> > 224.1.1.1
> > PIM(0): Received v2 Join/Prune on FastEthernet0/0 from 35.35.35.5, to
> > us
> > PIM(0): Join-list: (*, 224.0.1.40), RPT-bit set, WC-bit set, S-bit set
> > PIM(0): Update FastEthernet0/0/35.35.35.5 to (*, 224.0.1.40), Forward
> > state, by PIM *G Join
> > PIM(0): Send RP-reachability for 224.0.1.40 on FastEthernet0/0
> > PIM(0): Send RP-reachability for 224.0.1.40 on Serial1/0
> > PIM(0): Building Periodic (*,G) Join / (S,G,RP-bit) Prune message for
> > 224.2.2.2
> > PIM(0): Received v2 Register on FastEthernet0/0 from 35.35.35.5
> > PIM(0): Send v2 Register-Stop to 35.35.35.5 for 0.0.0.0, group 0.0.0.0
> >
> >
> >
> > **R1 is neither receiving the join message nor does it have an entry
> > for the (*,G)*
> >
> > R1(config-if)#do sh ip mroute 224.6.6.6 Group 224.6.6.6 not found
> >
> >
> > *MORE OUTPUT*
> >
> > R2(config)#do sh frame map
> > Serial1/0 (up): ip 10.10.10.1 dlci 201(0xC9,0x3090), static,
> > broadcast,
> > CISCO, status defined, active
> > Serial1/0 (up): ip 10.10.10.2 dlci 201(0xC9,0x3090), static,
> > CISCO, status defined, active
> > Serial1/0 (up): ip 10.10.10.3 dlci 201(0xC9,0x3090), static,
> > CISCO, status defined, active
> >
> >
> > R3(config)#do sh frame map
> > Serial1/0 (up): ip 10.10.10.1 dlci 301(0x12D,0x48D0), static,
> > broadcast,
> > CISCO, status defined, active
> > Serial1/0 (up): ip 10.10.10.2 dlci 301(0x12D,0x48D0), static,
> > CISCO, status defined, active
> >
> >
> > R2(config)#do sh ip route
> > Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
> > D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
> > N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
> > E1 - OSPF external type 1, E2 - OSPF external type 2
> > i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS
> > level-2
> > ia - IS-IS inter area, * - candidate default, U - per-user static
> > route
> > o - ODR, P - periodic downloaded static route
> >
> > Gateway of last resort is not set
> >
> > 1.0.0.0/32 is subnetted, 1 subnets
> > O 1.1.1.1 [110/65] via 10.10.10.1, 00:37:27, Serial1/0
> > 35.0.0.0/24 is subnetted, 1 subnets
> > O 35.35.35.0 [110/65] via 10.10.10.3, 00:37:27, Serial1/0
> > 2.0.0.0/32 is subnetted, 1 subnets
> > C 2.2.2.2 is directly connected, Loopback1
> > 3.0.0.0/32 is subnetted, 1 subnets
> > O 3.3.3.3 [110/65] via 10.10.10.3, 00:37:27, Serial1/0
> > 4.0.0.0/32 is subnetted, 1 subnets
> > O 4.4.4.4 [110/2] via 24.24.24.4, 00:37:27, FastEthernet0/0
> > 5.0.0.0/32 is subnetted, 1 subnets
> > O 5.5.5.5 [110/66] via 10.10.10.3, 00:37:27, Serial1/0
> > 24.0.0.0/24 is subnetted, 1 subnets
> > C 24.24.24.0 is directly connected, FastEthernet0/0
> > 10.0.0.0/24 is subnetted, 1 subnets
> > C 10.10.10.0 is directly connected, Serial1/0
> >
> >
> >
> >
> >
> >
> > R3(config)#do sh ip route
> > Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
> > D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
> > N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
> > E1 - OSPF external type 1, E2 - OSPF external type 2
> > i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS
> > level-2
> > ia - IS-IS inter area, * - candidate default, U - per-user static
> > route
> > o - ODR, P - periodic downloaded static route
> >
> > Gateway of last resort is not set
> >
> > 1.0.0.0/32 is subnetted, 1 subnets
> > O 1.1.1.1 [110/65] via 10.10.10.1, 00:36:54, Serial1/0
> > 35.0.0.0/24 is subnetted, 1 subnets
> > C 35.35.35.0 is directly connected, FastEthernet0/0
> > 2.0.0.0/32 is subnetted, 1 subnets
> > O 2.2.2.2 [110/65] via 10.10.10.2, 00:36:54, Serial1/0
> > 3.0.0.0/32 is subnetted, 1 subnets
> > C 3.3.3.3 is directly connected, Loopback1
> > 4.0.0.0/32 is subnetted, 1 subnets
> > O 4.4.4.4 [110/66] via 10.10.10.2, 00:36:54, Serial1/0
> > 5.0.0.0/32 is subnetted, 1 subnets
> > O 5.5.5.5 [110/2] via 35.35.35.5, 00:36:54, FastEthernet0/0
> > 24.0.0.0/24 is subnetted, 1 subnets
> > O 24.24.24.0 [110/65] via 10.10.10.2, 00:36:54, Serial1/0
> > 10.0.0.0/24 is subnetted, 1 subnets
> > C 10.10.10.0 is directly connected, Serial1/0
> >
> >
> >
> >
> >
>
>
> --
> Warm wishes,
>
> Ty.
>
>
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-- 
Warm wishes,
Ty.
Blogs and organic groups at http://www.ccie.net