H3C Technologies H3C S10500 Series Switches - Manual (Page 139)

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IGMP proxy is enabled
Current IGMP version is 2
Multicast routing on this interface: enabled
Require-router-alert: disabled
Version1-querier-present-timer-expiry: 00:00:20
Use the display igmp group command to view the IGMP group information. For example,
# Display the IGMP group information on Switch A.
[SwitchA] display igmp group
Total 1 IGMP Group(s).
Interface group report information of VPN-Instance: public net
Vlan-interface100(192.168.1.1):
Total 1 IGMP Groups reported
Group Address Last Reporter Uptime Expires
224.1.1.1 192.168.1.2 00:02:04 00:01:15
The output shows that IGMP reports from the hosts are forwarded to Switch A through the proxy interface,
VLAN-interface 100 on Switch B.
Troubleshooting IGMP
No membership information on the receiver-side router
Symptom
When a host sends a report for joining multicast group G, no membership information of the multicast
group G exists on the router closest to that host.
Analysis
• The correctness of networking and interface connections and whether the protocol layer of the
interface is up directly affect the generation of group membership information.
• Multicast routing must be enabled on the router, and IGMP must be enabled on the interface
connecting to the host.
• If the IGMP version on the router interface is lower than that on the host, the router will not be able
to recognize the IGMP report from the host.
• If the igmp group-policy command has been configured on the interface, the interface cannot
receive report messages that fail to pass filtering.
Solution
1. Check that the networking, interface connection, and IP address configuration are correct. Check
the interface information with the display igmp interface command. If no information is output, the
interface is in an abnormal state. This is usually because you have configured the shutdown
command on the interface, the interface is not properly connected, or the IP address configuration
is not correct.
2. Check that multicast routing is enabled. Use the display current-configuration command to check
whether the multicast routing-enable command has been executed. If not, carry out the multicast
routing-enable command in system view to enable IP multicast routing. In addition, check that
IGMP is enabled on the corresponding interfaces.