Troubleshooting Igmp Snooping - H3C S7500 Series Operation Manual

Operation Manual – Multicast
H3C S7500 Series Ethernet Switches
[H3C-vlan1024] multicast-vlan enable
[H3C-vlan1024] quit
[H3C] multicast-vlan 1024 subvlan 2 to 7

3.5 Troubleshooting IGMP Snooping

Symptom: Multicast does not work on the switch.
Solution:
The reason may be:
1) IGMP Snooping is not enabled.
Use the display current-configuration command to check the status of IGMP
Snooping.
If IGMP Snooping is disabled, check whether it is disabled globally or in the
corresponding VLAN. If it is disabled globally, use the igmp-snooping enable
command in both system view and VLAN view to enable it both globally and in the
corresponding VLAN at the same time. If it is only disabled in the corresponding
VLAN, use the igmp-snooping enable command in VLAN view only to enable it
in the corresponding VLAN.
2) Multicast forwarding tables set up by IGMP Snooping are wrong.
Use the display igmp-snooping group command to check if the multicast groups
are expected ones.
If the multicast group set up by IGMP Snooping is not correct, contact your
technical support personnel.
Continue with solution 3) if the second step does not work.
If it is not the reason, the possible reason may be:
3) MAC multicast forwarding tables set up by IGMP Snooping are wrong.
Use the display mac-address vlan command to check whether the MAC
multicast forwarding table set up in the VLAN view identified by the vlan-id
argument is consistent with the one set up by IGMP Snooping.
If they are not consistent, contact your technical support personnel.
Chapter 3 IGMP Snooping Configuration
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