RE: PIM Neighbor

Can't really make out the topology below, but have you verified your
frame-relay connectivity? Are you sure you haven't left unnecessary
frame-relay mappings in place that could have been learned with inverse ARP?

Aundra (Andre) Browning
CCIE #21901 (R&S)

-----Original Message-----
From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of
Anantha Subramanian Natarajan
Sent: Wednesday, July 08, 2009 12:02 AM
To: Cisco certification
Subject: PIM Neighbor

Hi All,

   I have a question based on the lab exercise task which I was doing.The
physical topology looks like below

                                               R1
                                                |
    R2(Hub-183.1.123.2/24) ---FR Cloud -------(
183.1.123.3/24)R3(183.1.0.3/24) ------------ FR Cloud ------
-R5(Hub-183.1.0.5/24)

                                               |

                                                                     R4

    PIM sparse-dense-mode is configured on R2 ,R3 and R5 serial frame-relay
interfaces in addition to enabling on R2,R3 loopback0 interface.R2 is asked
to configure as Mapping agent fo auto-rp and R3 is asked to configure as
auto-rp for all the multicast goup.Was able to test multicast by joining a
groupon R5 ethernet interface which is also enabled for PIM by pinging from
R2 ethernet interface enabled for PIM.

The question is ,1) when I performed "show ip pim neighbor command" on R5,I
see both R3 ip address 183.1.0.3 and R2 ip address 183.1.123.3.I am trying
to understand,why it show the R2 ip address on it.

Rack1R5#sh ip pim neighbor
PIM Neighbor Table
Mode: B - Bidir Capable, DR - Designated Router, N - Default DR Priority,
      S - State Refresh Capable
Neighbor Interface Uptime/Expires Ver DR
Address Prio/Mode
*183.1.123.2 Serial0/0 00:08:02/00:01:33 v2 1 / DR S
*183.1.0.3 Serial0/0 00:08:12/00:01:23 v2 1 / S

2) Also on R3,the show ip pim neighbor o/p is as below

    Rack1R3#sh ip pim neighbor
PIM Neighbor Table
Mode: B - Bidir Capable, DR - Designated Router, N - Default DR Priority,
      S - State Refresh Capable
Neighbor Interface Uptime/Expires Ver DR
Address Prio/Mode
183.1.123.2 Serial1/0 00:10:07/00:01:27 v2 1 / S
183.1.0.5 Serial1/1 00:07:20/00:01:29 v2 1 / S
183.1.123.2 Serial1/1 00:09:37/00:01:27 v2 1 / DR S

I am not sure,why it showing 183.1.123.2 learned through both on S1/0 and
S1/1.I ran debug ip pim hello and on the debug o/p,I am able to see hello
received from 183.1.123.2 on both s1/1 and s1/0.I couldn't understand
that.Any help is really appreciated.

Rack1R3#debug ip pim hello
PIM-HELLO debugging is on
Rack1R3#
*Mar 1 01:33:46.092: PIM(0): Received v2 hello on Serial1/0 from
183.1.123.2
Mar 1 01:33:46.092: PIM(0): Neighbor (183.1.123.2) Hello GENID = 2740287763
Mar 1 01:33:46.100: PIM(0): Received v2 hello on Serial1/1 from 183.1.123.2
Mar 1 01:33:46.100: PIM(0): Neighbor (183.1.123.2) Hello GENID = 2740287763
*Mar 1 01:33:48.372: PIM(0): Received v2 hello on Serial1/1 from 183.1.0.5
Mar 1 01:33:48.376: PIM(0): Neighbor (183.1.0.5) Hello GENID = 706508139
Mar 1 01:33:49.124: PIM(0): Send periodic v2 Hello on Serial1/0 with GenID
= 2915304491

Thanks for the help.

Regards
Anantha Subramanian Natarajan

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Received on Wed Jul 08 2009 - 12:17:55 ART