Symptom/Cause | Solution |
|---|---|
IGMP Report not learned IGMP Snooping disabled globally. IGMP Snooping disabled on vlan interface. Port on which report is sent in discarding state (xSTP). Destination MAC of the frame does not correspond to Destination IP multicast address. TTL of the IP packet not 1. For IGMPv3 report destination address of IP packet not 224.0.0.22. | Use these commands: show igmp snooping interface Check if IGMP snooping is enabled globally and on interface. If underlying L2 interface is in forwarding state in spanning tree then it will be listed below vlan interface. show running-config Confirm if igmp snooping is disabled globally or on interface. |
IGMP reports forwarded by switch Snooping switch sending reports only when it receives an IGMP query | Use these commands: show igmp snooping mrouter VLAN-IFNAME Confirm mrouter interface learned |
IGMP Queries sent with Source IP as zero Switch sending queries with SIP as 0 when it is configured as querier, otherwise queries received from router will be forwarded as is to all interfaces bound to that VLAN. | Use these commands: show igmp snooping interface VLAN-IFNAME Check if querier is enabled on the interface show running-config Confirm the configuration of querier. |
Traffic not forwarded from the source specified in the IGMP membership Report. The resulting state of the source might be in exclude list OR The group might have been expired | Use these commands: show igmp snooping groups detail Confirm if the source is in exclude list or include list of the Group and to check expiry timer, if it is dynamic group then it will not be shown in this command after expiry. |