Igmp Snooping Configuration Example; Troubleshooting Igmp Snooping - 3Com Switch 7700 Configuration Manual

210 C 6: M
HAPTER ULTICAST
IGMP Snooping
Configuration Example
Troubleshooting IGMP
Snooping
P
ROTOCOL
To implement IGMP Snooping on the switch, first enable it. The switch is
connected with the router through the router port, and with user PC through the
non-router ports.
Figure 6 IGMP Snooping Configuration Network
A router running
IGMP
An Ethernet switch
running IGMP
snooping
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
■
IGMP Snooping.
If the switch disabled IGMP Snooping, you can input igmp-snooping enable
■
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 see if the multicast
■
group is the expected one.
Verify that the source IP address is correct for each multicast stream.
■
3 Multicast forwarding table set up on the bottom layer is wrong.
Enable IGMP Snooping group in user view and then input the display
■
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.
Internet
IGMP packets
IGMP packets