From: Ronnie Royston (RonnieR@xxxxxxxxxxxxxxxxx)
Date: Mon Nov 06 2000 - 17:30:24 GMT-3
Frog, I set up a similar lab, every interface in dense mode. My design is:
____R3
/
R1-----R2<
\____
R4
R2 to R3 & R4 is nbma. I have an 'ip igmp join 227.7.7.7' on R1 and R4's
Lo0 interfaces. With a clean mroute table, if I ping 227.7.7.7 from R4, I
get the following mroute table (from R4):
(*, 227.7.7.7), 00:00:16/00:00:00, RP 0.0.0.0, flags: DJCL
Incoming interface: Null, RPF nbr 0.0.0.0
Outgoing interface list:
Serial0.1, Forward/Dense, 00:00:16/00:00:00
Loopback0, Forward/Dense, 00:00:16/00:00:00
(4.1.1.1, 227.7.7.7), 00:00:12/00:02:48, flags: PCLT
Incoming interface: Loopback0, RPF nbr 0.0.0.0
Outgoing interface list:
Serial0.1, Prune/Dense, 00:00:12/00:02:48
(4.1.2.1, 227.7.7.7), 00:00:15/00:02:44, flags: CLT
Incoming interface: Loopback1, RPF nbr 0.0.0.0
Outgoing interface list:
Loopback0, Forward/Dense, 00:00:15/00:00:00
Serial0.1, Prune/Dense, 00:00:15/00:02:45
>From this table, it is clear that the router thinks there are no members of
this group on the network? It is my understanding that when multicast
traffic is generated in dense mode, all PIM-DM routers initially get the
traffic. Here's the mroute table from the nearest upstream neighbor (R2)
after that ping from R4:
(*, 227.7.7.7), 00:09:00/00:02:59, RP 0.0.0.0, flags: D
Incoming interface: Null, RPF nbr 0.0.0.0
Outgoing interface list:
Serial0/0, Forward/Dense, 00:09:00/00:00:00
(4.1.1.1, 227.7.7.7), 00:00:09/00:02:50, flags: PTA
Incoming interface: Serial0/0, RPF nbr 20.1.1.3
Outgoing interface list: Null
(4.1.2.1, 227.7.7.7), 00:00:11/00:02:48, flags: PTA
Incoming interface: Serial0/0, RPF nbr 20.1.1.3
Outgoing interface list: Null
(20.1.1.3, 227.7.7.7), 00:00:12/00:02:47, flags: PTA
Incoming interface: Serial0/0, RPF nbr 0.0.0.0
Outgoing interface list: Null
That's bulls*#t ! There is a member of that group a little bit further up.
R4 knows the RPF path to R1's Lo0 int (the home of the 227.7.7.7 join),
here's a 'sho ip rpf 1.1.2.2' (the ip of the Lo0 int):
sleepy#sho ip rpf 1.1.2.2
RPF information for ? (1.1.2.2)
RPF interface: Serial0.1
RPF neighbor: ? (20.1.1.2)
RPF route/mask: 1.0.0.0/255.0.0.0
RPF type: unicast
I am confused and frustrated and ....damn multicasting is difficult! What's
the dilio? Can somebody please explain? What am I missing???
-----Original Message-----
From: Frog.Leu@datacraft-asia.com [mailto:Frog.Leu@datacraft-asia.com]
Sent: Monday, November 06, 2000 8:41 AM
To: Ronnie Royston
Cc: Frog.Leu@datacraft-asia.com
Subject: ?? : Multicast ping replies
Hi Sir,
I am Frog from Taiwan. I have tried the multicast in Frame-relay
many times but failed and failed again! Espically in RP in Spoke-1 and igmp
join Spoke-2, it does not work by using Ping. Could you explain why? Or any
suggestion? I have configured it as NBMA mode in hub and spokes. Is it
nessary configured "ip pim nbma" "ONLY IN" hub of frame-relay?
Please give me a hint or samples! Thanks you very much!!
Frog Leu
Network Integration Engineering Team Manager
Datacraft Taiwan Limited
3F-7, 188, Sec5, Nan-King E. Rd.,
Taipei, Taiwan, R.O.C.
Tel : 886-2-27609696#119
Fax : 886-2-27568686
E-mail : frog.leu@datacraft-asia.com
> -----鴝l郵件-----
> 寄件者: Ronnie Royston [SMTP:RonnieR@globaldatasys.com]
> 傳送時間: 2000年11月6日 AM 03:48
> 收件者: 'radha rani'; ccielab@groupstudy.com
> 主旨: RE: Multicast ping replies
>
> Are you sure that inverse arp didn't make a full mesh? Are you running
> dense, sparse, or sparse-dense? Do you have 'ip pim nbma-mode' configured
> on the hub interface?
>
> -----Original Message-----
> From: radha rani [mailto:radhaccie@hotmail.com]
> Sent: Saturday, November 04, 2000 7:09 PM
> To: ccielab@groupstudy.com
> Subject: Multicast ping replies
>
>
> I have 4 routers configured in a multicast group. 1 FR hub with three
> spokes.
>
> Why is it that when I ping the multicast address from the hub router, i
> get
> three responses - one from each hub. But when I ping from a spoke router,
> I
>
> get THREE responses from each member og the multicast group.
> On each spoke router, only one lan interface is included in the m-cast
> group. Can someone explain. Thanks in advance.
>
> -Radha
This archive was generated by hypermail 2.1.4 : Thu Jun 13 2002 - 08:25:42 GMT-3