Troubleshooting Igmp Snooping - 3Com 4200G 12-Port Configuration Manual

Troubleshooting IGMP
Snooping
[ Switch B-GigabitEthernet 1/0/1] quit
e Define the GigabitEthernet 1/0/2 port as a hybrid port, add the port to VLAN 3
and VLAN 10, and configure the port to exclude VLAN tags in its outbound
packets for VLAN 3 and VLAN 10, and set VLAN 3 as the default VLAN of the port.
[ Switch B] interface GigabitEthernet 1/0/1
[ Switch B-GigabitEthernet 1/0/2] port link-type hybrid
[ Switch B-GigabitEthernet 1/0/2] port hybrid vlan 3 10 untagged
[ Switch B-GigabitEthernet 1/0/2] port hybrid pvid vlan 3
[ Switch B-GigabitEthernet 1/0/2] quit
Symptom: Multicast function 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 on 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 on
the corresponding VLAN. If it is only disabled on the VLAN, use the
igmp-snooping enable command in VLAN view to enable it on the
corresponding VLAN.
2 Multicast forwarding table set up by IGMP Snooping is wrong.
Use the display igmp-snooping group command to check if the multicast
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groups are expected ones.
If a multicast group created by IGMP Snooping is not correct, contact your
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technical support personnel.
Continue with step 3 if the this step does not work.
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If it is not the reason, the possible reason may be:
3 Multicast forwarding tables do not match.
Use the display mac-address vlan vlanid command in any view to check if the
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MAC multicast forwarding table established under the specified VLAN is
consistent with that established by IGMP Snooping.
If they are not consistent, contact your technical support personnel.

Troubleshooting IGMP Snooping 259