Showing results for 
Search instead for 
Did you mean: 


Oleksandr Y.

Hello Community, another conundrum that I am trying to solve - seems like I am very close to solution but there might be some concepts I don't have a full grasp on - so asking help from the community Here is a visual: 


 Below is all the related config I have on the L3 SW (CISCO 9300)


ip multicast-routing vrf SAT-EDGE distributed


interface Vlan106
ip vrf forwarding SAT-EDGE
ip address
ip pim passive
load-interval 30


interface Vlan254
ip vrf forwarding SAT-EDGE
ip address
ip pim dense-mode
ip igmp static-group
load-interval 30


My LAB is a little bit more complicated than this, but I wanted to simplify and FOCUS on what is not working actually. I don't have any equipment capable of IGMP so I am using mostly static configurations everywhere. 

In a nutshell when I launch Multicast Traffic from the Source I am seeing it arrive on interface VLAN106 (I will actually have multiple sources eventually, such as VLAN 206, 306, etc... ) but the Receivers are all downstream of this VLAN 254 interface.

In the output of "ip mroute ..." I am not seeing an ingress interface and I am sure I am missing something either VRF Related configuration to support Multicast or vice-versa, but I can not seem to put my finger on it


L2-SW-9300#sh ip mroute vrf SAT-EDGE
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,
G - Received BGP C-Mroute, g - Sent BGP C-Mroute,
N - Received BGP Shared-Tree Prune, n - BGP C-Mroute suppressed,
Q - Received BGP S-A Route, q - Sent BGP S-A Route,
V - RD & Vector, v - Vector, p - PIM Joins on route,
x - VxLAN group
Outgoing interface flags: H - Hardware switched, A - Assert winner, p - PIM Join
Timers: Uptime/Expires
Interface state: Interface, Next-Hop or VCD, State/Mode

(*,, 17:22:45/stopped, RP, flags: DC
Incoming interface: Null, RPF nbr
Outgoing interface list:
Vlan254, Forward/Dense, 16:48:10/stopped

(*,, 17:31:46/00:02:38, RP, flags: DCL
Incoming interface: Null, RPF nbr
Outgoing interface list:
Vlan254, Forward/Dense, 17:31:46/stopped

Any ideas will be very much appreciated  

2 Replies 2

Giuseppe Larosa
Hall of Fame Master Hall of Fame Master
Hall of Fame Master

Hello @Oleksandr Y. ,


why you have ip pim passive under interface VLAN 106 could you try to use ip pim dense-mode instead ?



check the TTL of the multicast sources must be greater then 1 or they are silently dropped on the switch


Hope to help




Hi again Giuseppe seems like you are the main responder on my questions Thanks for that. 

I tried all kinds of combinations, ip pim passive works fine as well because I have it set up further upstream (closer to the multicast source) and it does the job - but yes I have tried ip pim dense everywhere to no avail. 


TTL is set properly as well - we discussed this in one of the previous posts


Any other ideas ? I mean I see the traffic coming in on VLAN 106 - I see Multicast packet count ... and since this interface and Interface Vlan254 are both in the same VRF I figured by forcing Vlan254 interface to send traffic out of it using the "ip igmp static-group" would actually work ... I even tried disabling ip igmp snooping for vlan 254 and 106 but still no luck  

Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community:

Recognize Your Peers