Troubleshootinigmp Snooping; Common Multicast Configuration - 3Com 7700 Configuration Manual

TroubleshootinIGMP
Snooping
Common Multicast
Configuration
Figure 7 IGMP Snooping Configuration Network
Internet
Router
Switch
1 Display the status of GMRP.
<SW7700> display gmrp status
2 Display the current status of IGMP Snooping when GMRP is disabled.
<SW7700> display igmp-snooping configuration
3 Enable IGMP Snooping if it is disabled.
[SW7700] igmp-snooping enable
If the multicast function cannot be implemented on the switch, check for the
following conditions and use the accompanying troubleshooting procedure:
1 IGMP Snooping is disabled.
Input the display current-configuration command to display the status of
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IGMP Snooping.
If the switch disabled IGMP Snooping, you can input igmp-snooping enable
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in the system view to enable IGMP Snooping.
2 Multicast forwarding table set up by IGMP Snooping is wrong.
Input the display igmp-snooping group command to display if the multicast
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group is the expected one.
If the multicast group created by IGMP Snooping is not correct, turn to
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professional maintenance personnel for help.
Continue with diagnosis 3 if the second step is completed.
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3 Multicast forwarding table set up on the bottom layer is wrong.
Enable IGMP Snooping group in user view and then input the display
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igmp-snooping group command to check if MAC multicast forwarding table
in the bottom layer and that created by IGMP Snooping is consistent. You may
also input the display mac vlan command in all views to check if MAC
multicast forwarding table under vlanid in the bottom layer and that created by
IGMP Snooping is consistent.
If they are not consistent, contact the maintenance personnel for help.
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A common multicast configuration covers both the multicast group management
protocol and the multicast routing protocol. The configuration includes enabling
multicast, configuring multicast forwarding boundary, and displaying multicast
routing table and multicast forwarding table.
Multicast

Common Multicast Configuration

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