Multicast VLAN clients not talking to the server

[James Simpson]

Multicast within a vlan not working

Hi

I have a 3850 switch with vlan 18 that I want to enable multicast on 

Off this witch I have a couple of 2960 stacks

(3850)

interface vlan 18 

ip address 192.168.1.1 255.255.255.0

ip pim sparse-mode

!

ip pim rp-address 192.168.1.1 
!
ip multicast-routing
!
ip igmp snooping querier

All other switches 

!

ip igmp snooping querier

!

ip pim rp-address 192.168.1.1 
!
ip multicast-routing

I need a a couple of clients to access a server with vlan 18, and they cant seem to communicate 

is there something im missing 

Thanks in advance 

[James Simpson]

Hi

I have a 3850 switch with vlan 18 that I want to enable multicast on 

Off this witch I have a couple of 2960 stacks

(3850)

interface vlan 18 

ip address 192.168.1.1 255.255.255.0

ip pim sparse-mode

!

ip pim rp-address 192.168.1.1 
!
ip multicast-routing
!
ip igmp snooping querier

All other switches 

!

ip igmp snooping querier

!

ip pim rp-address 192.168.1.1 
!
ip multicast-routing

I need a a couple of clients to access a server with vlan 18, and they cant seem to communicate 

is there something im missing 

Thanks in advance 

[Giuseppe Larosa]

Hello James,

you don't need the IGMP snooping querier because the C3850 SVI interface has PIM enabled and this enables IGMP too (version 2 by default).

You need also to know that in a given Vlan only one device can be configured with the IGMP snooping querier command (there is no way to perform an election of the best IGMP snooping querier).

Try again removing all the IGMP snooping querier commands

Hope to help

Giuseppe

[brselzer]

Hello James,

Are the 2960s L2 only? If so, they don't need the PIM config. Also, you only want one querier in a vlan and enabling PIM on an interface enables it as a querier so you can remove "ip igmp snooping querier" from all switches as "ip pim sparse-mode" automatically enables it for you. 

The clients and the source server are both in vlan 18? I assume unicast from the source server to the clients work?

Hope that helps!

[James Simpson]

Hi 

Unicast  is already in place , the multicast is allowing expansion of devices to talk to the server 

All 2960s are L2 

Cisco IOS Software, C2960X Software (C2960X-UNIVERSALK9-M), Version 15.2(2)E7, R ELEASE SOFTWARE (fc3)

[James Simpson]

Hi All 

Sorry all L2 switches are configured ip igmp snooping querier only

[brselzer]

Hello James,

Are the source and receiver in the same vlan? You only want one querier in a vlan. You should remove it from all the L2 switches and leave it on the 3850.

Hope that helps!!