Multicast Routing Pim-Sparse-Mode

[ashleyreed4218]

Hi All,

If I put ip pim-sparse-mode on an interface, and then issue a show ip mroute command and don't see the interface there, is that sufficient evidence to suggest that the interface isn't seeing the multicast?

Thank you in advance,

AR

[John Blakley · Accepted solution]

You need to make sure that you enable multicast routing globally. You'd be able to put the command on the interface, but you should receive an error. If you put the command on the interface and do a "sho ip mroute", you won't see anything until you enable multicast routing with "ip multicast-routing" in global mode. After you do this, you should see the router listening for 224.0.1.40

(*, 224.0.1.40), 00:00:03/00:02:56, RP 0.0.0.0, flags: DCL

  Incoming interface: Null, RPF nbr 0.0.0.0

  Outgoing interface list:

    FastEthernet0/0, Forward/Sparse, 00:00:03/00:02:56

HTH,

John

[ashleyreed4218]

Thank You John,

I tried to go into global:

ROUTER1(config)#ip pim sparse ?

It wont let me issue the pim sparse-mode command? Am I doing something wrong?

[John Blakley]

The "ip pim sparse" command goes under the interface that you want to enable pim on. You'd enable "ip multicast-routing" at the global level:

R2(config)#ip multicast-routing

R2(config)#int fa0/0

R2(config-if)#ip pim sparse

R2(config-if)#ip pim sparse-

R2(config-if)#do sh ip m

*Mar  1 01:00:08.483: %PIM-5-DRCHG: DR change from neighbor 0.0.0.0 to 192.168.12.2 on interface FastEthernet0/0r

R2(config-if)#do sh 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,

       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

(*, 224.0.1.40), 00:00:03/00:02:58, RP 0.0.0.0, flags: DCL

  Incoming interface: Null, RPF nbr 0.0.0.0

  Outgoing interface list:

    FastEthernet0/0, Forward/Sparse, 00:00:03/00:02:58

R2(config-if)#

HTH,

John

[ajay chauhan]

As John suggested - Multicast routing should be enabled in global config and then PIM on per interface basis.

Once configured number of interfaces can also be checked configured for PIM with command-

sh ip pim interface

Thanks

Ajay