Multicast - Cisco N5K-M1600 - Expansion Module - 6 Ports Troubleshooting Manual

Chapter 3 Troubleshooting Layer 2 Switching Issues
S e n d d o c u m e n t c o m m e n t s t o n e x u s 5 k - d o c f e e d b a c k @ c i s c o . c o m .
Solution
Check the native VLAN configured at both ends (ports) of the link. Ensure that they have the same native
VLAN. Once the native VLANs are synchronized, the port moves out of the inconsistency state.

Multicast

Source MAC addresses of IGMP joins are learned
In this situation, the source MAC addresses of IGMP joins are learned. However, source MAC addresses
of IGMP joins are usually not learned by the switch in order to conserve MAC address space.
Possible Cause
Receiving joins and performing an ISSU simultaneously might cause the situation.
Solution
The MAC addresses age out (expire) if the join stops. Alternatively, you can clear the MAC addresses
specifically by using the clear mac address-table dynamic mac <mac> command.
Multicast data traffic not received by host
Host does not receive multicast data traffic.
Possible Cause
The join is not registered.
Solution
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Multicast data traffic not received when host is registered for group
Multicast data traffic is not received when the host is registered for the group.
Possible Cause
A bug may exist in exist in the communication between the IGMP and FWM processes.
Review the output from the following commands:
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Solution
OL-25300-01
Ensure that the host application is sending the joins.
Check if the switch port is configured for the VLAN on which the joins are being sent using the
show vlan id <vlan> command.
Check if the relevant VLAN is active by using the show vlan id <vlan> command.
Check if the switch port is in STP forwarding state by using the show spanning-tree vlan <vlan>
command.
show ip igmp snooping groups vlan 1001
show mac address-table multicast vlan 1001 igmp-snooping
show platform fwm info vlan 1001 all_macgs verbose
Cisco Nexus 5000 Series Troubleshooting Guide
Multicast
3-5