Multicast address 239.4.1.0

[Warren]

I am trying to troubleshoot an multicast issue with the group IP of 239.4.1.58 but when I enter the following commands
at the FHR I get nothing

sh ip igmp group 239.4.1.58
sh ip mroute 239.4.1.58
sh ip mfib 239.4.1.58

when I ask if there is a group that is working they told me 239.4.1.39
but when I enter the above commands for the .39 I don’t see anything
why is that? The server that is sourcing the multicast group is directly connected

to the switch so not sure why I cannot see this.

I tried a different mcast group that I found was working 239.18.1.113
when I enter the same commands I get information. I just don’t see anything
for the 239.4.1.39 or 58 groups. Am I doing something wrong?

Thank you in advance!!!

[brselzer]

Hello Warren,

Are the source and receiver on the same vlan? If so, mroute and mfib won't show you anything. Try the following command:

show ip igmp snooping groups

Can you also paste the config for the vlan that the server is in? 

Hope that helps!

[Warren]

No the source sits on vlan550 in frankfurt and the receiver is here in chicago on vlan 201

SW-FRCL-CORE1#sh ip igmp snoo grou
Vlan Group Type Version Port-List
--------------------------------------------------------------------------------
550 224.0.1.129 Dynamic - Cpu, Et22, Et7
550 239.18.1.113 Dynamic - Cpu, Et21, Et9
550 239.18.3.1 Dynamic - Cpu, Et12, Et13, Et14, Et15,
Et16, Et17, Et21, Et4, Et7,
Et8, Et9
550 239.18.3.3 Dynamic - Cpu, Et23
550 239.96.1.3 Dynamic - Cpu, Et23, Et9
550 239.96.1.5 Dynamic - Cpu, Et23, Et9
550 239.96.1.6 Dynamic - Cpu, Et13, Et16, Et23, Et4,
Et8
550 239.96.1.33 Dynamic - Cpu, Et12
550 239.96.1.41 Dynamic - Cpu, Et14
550 239.96.1.49 Dynamic - Cpu, Et17
550 239.96.4.6 Dynamic - Cpu, Et9

[Warren]

sorry left out the vlan config

SW-FRCL-CORE1#sh run inter vlan 550
interface Vlan550
description 10.97.10.0/24-Trade-LAN2
ip address 10.97.10.254/24
ip dhcp relay client
ip pim sparse-mode

[brselzer · Accepted solution]

Hello Warren,

I understand now. You won't see anything in the snooping groups if only the source is connected to this switch. Do you have any special PIM configuration that would restrict what groups you are routing?

show ip pim rp mapping

What kind of switch is this? Model and version? 

Hope that helps!

[Warren]

sh ip pim rp

Group: 239.4.0.0/15Group: 239.4.0.0/15  RP: 10.16.160.20    Uptime: 968d16h, Expires: never, Override: 0

[Warren]

oh wait you know what I am on an arista switch sorry but amazingly enough the cisco 

commands work.  I don't see any special routing that would prevent it. That is weird 

why 239.4.1.39 works but now 239.4.1.58.  Anyways thank you for your help let me

ask the arista guys.  Sorry I forgot we had arsita switches as well.  But appreciate the 

help!!!

[Warren]

Just a FYI I rechecked the PIM RP and fond out that I had 2 entries

ip pim rp-address 10.16.160.20 239.4.0.0/15

ip pim rp-address 10.103.68.1 239.4.1.58/32

the more specific one was the issue as that is a dead so when I removed the specific one

ip pim rp-address 10.103.68.1 239.4.1.58/32

all worked.  Thank you breslzer for your help even though it was on another platform 

Thank you sir!!!!!