IP MULTICAST==PIM-SM

[sameermunj]

Hi Team

I am trting to test multicast between two sites connected over WAN...SIte A is connected to Site B with DS3 link with  ethernet output.The DS3 link is connncteted between cisco 2851 router at each end.

At Lan SIde Cisco 2851 router is conncted to Nortel-8600 Switch over ethernet connectivty at both end.PIM is enabled on Nortel-8600 core switch  with Sparse mode and multicast is working fine within LAN.Same is the result for both sites.

Now we are trying to make multicast work over wan in which PIM is enabled on both lan & want interafce of cisco router with sparse mode and multicast is enabled globally...now both the routers are making neighbourship with respective lan switches and with each other but multicast traffic is not flowing.In cisco router Mroute is not coming for the multicast group defined in core switch..

Please suggest necessary changes for the same if any...

Note

Multicast is working fine within LAN for each site bbut its not working between 2 lans over wan...

LAN A====Core Switch A==Router A =====Metro Link Router B==Core Switch B==LAN B

we are trying Multicast between LAN A & LAN B.

[Peter Paluch]

Hello Sameer,

As you have not included configs of your devices nor any command outputs, we can only guess the real reason of your problems. Nevertheless, try to go over the following steps to narrow down the cuase of the issue:

1. Make sure that the IP multicast routing is activated on all routers and all proper interfaces (ip multicast-routing [distributed]; ip pim sparse-mode)
   
2. Make sure that the RP is properly known on all routers including the RP itself (show ip pim rp mapping)
3. Make sure that all routers know about the network in which the multicast sender is located (show ip route)
4. After starting the multicast receiver application at the Site B, verify on the Router B that it knows about the multicast group that the receiver has subscribed into, and that the multicast routing table has created an entry with the oif list including the interface towards LAN B (show ip igmp group; show ip mroute)
5. Verify that the Router B has joined the shared tree rooted at the rendezvous point (probably the Router A) by verifying the show ip mroute on the Router A - the oif list for the appropriate multicast group should contain the interface towards Router B.
6. Start the multicast sender application at Site A and verify whether an (S,G) state has been created in the Router A's multicast routing table that forwards the multicast data towards Router B.

To eliminate possible problems with IGMP Snooping, try to deactivate it at the beginning on all switches in the network.

Please let us know about your findings.

Best regards,

Peter

[sameermunj]

Hi

RP has been configured in both the routers as Vlan io in core switch in which the multicast server is placed.

Please find below the mroute capture form both the routers.

Router A

Router A #show ip mroute
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, E - Extranet,
       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,
       V - RD & Vector, v - Vector
Outgoing interface flags: H - Hardware switched, A - Assert winner
Timers: Uptime/Expires
Interface state: Interface, Next-Hop or VCD, State/Mode

(*, 230.0.0.0), 00:04:21/00:02:35, RP 172.23.80.21, flags: SJCL
  Incoming interface: FastEthernet0/0/1, RPF nbr 172.29.1.21
  Outgoing interface list:
    GigabitEthernet0/0, Forward/Sparse-Dense, 00:04:21/00:02:35

(*, 224.0.1.40), 00:20:33/00:02:37, RP 0.0.0.0, flags: DCL
  Incoming interface: Null, RPF nbr 0.0.0.0
  Outgoing interface list:
    Loopback42, Forward/Sparse-Dense, 00:20:33/00:00:00
    FastEthernet0/0/0, Forward/Sparse-Dense, 00:20:33/00:00:00
    FastEthernet0/0/1, Forward/Sparse-Dense, 00:20:33/00:00:00
    GigabitEthernet0/0, Forward/Sparse-Dense, 00:20:33/00:00:00

Router A#show ip pim neighbor
PIM Neighbor Table
Mode: B - Bidir Capable, DR - Designated Router, N - Default DR Priority,
      P - Proxy Capable, S - State Refresh Capable, G - GenID Capable
Neighbor          Interface                Uptime/Expires    Ver   DR
Address                                                            Prio/Mode
10.232.65.21      GigabitEthernet0/0       02:41:15/00:01:36 v2    N /
172.29.1.21       FastEthernet0/0/1        02:37:30/00:01:39 v2    1 / S P G
172.31.1.21       FastEthernet0/0/0        02:37:41/00:01:30 v2    1 / S P G
INVDAB-DS3-RTR01#

Router B==== (Multicast server is in the switch connected to Router B)

Router B#show ip mroute
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, E - Extranet,
       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,
       V - RD & Vector, v - Vector
Outgoing interface flags: H - Hardware switched, A - Assert winner
Timers: Uptime/Expires
Interface state: Interface, Next-Hop or VCD, State/Mode

(*, 230.0.0.0), 00:05:28/00:03:10, RP 172.23.80.21, flags: SJCL
  Incoming interface: Null, RPF nbr 0.0.0.0
  Outgoing interface list:
    FastEthernet0/0/1, Forward/Sparse-Dense, 00:05:14/00:03:10
    GigabitEthernet0/0, Forward/Sparse-Dense, 00:05:28/00:01:50

(*, 224.0.1.40), 00:20:53/00:02:12, RP 0.0.0.0, flags: DCL
  Incoming interface: Null, RPF nbr 0.0.0.0
  Outgoing interface list:
    Loopback24, Forward/Sparse-Dense, 00:20:53/00:00:00
    FastEthernet0/0/1, Forward/Sparse-Dense, 00:20:53/00:00:00
    FastEthernet0/0/0, Forward/Sparse-Dense, 00:20:53/00:00:00
    GigabitEthernet0/0, Forward/Sparse-Dense, 00:20:53/00:00:00

Router B#show ip pim neighbor
PIM Neighbor Table
Mode: B - Bidir Capable, DR - Designated Router, N - Default DR Priority,
      P - Proxy Capable, S - State Refresh Capable, G - GenID Capable
Neighbor          Interface                Uptime/Expires    Ver   DR
Address                                                            Prio/Mode
172.23.80.7       GigabitEthernet0/0       02:38:13/00:01:31 v2    N /
172.23.80.6       GigabitEthernet0/0       02:38:14/00:01:31 v2    N /
172.31.1.22       FastEthernet0/0/0        02:38:28/00:01:19 v2    1 / DR S P G
172.29.1.22       FastEthernet0/0/1        02:38:16/00:01:27 v2    1 / DR S P G

attached is the config for both the routers...Multicast server is placed in the lan where Router B is conncted...

Note

Now Lan Switch A-Router A   Router A-Router B  RouterB-lan Switch B neighorship formed still traffic not passing..