3Com Switch 4800G 24-Port - Configuring an IGMP Snooping Policy

Configuring an IGMP Snooping Policy 565
Configuring IGMP queries and responses in a VLAN
Follow these steps to configure IGMP queries and responses in a VLAN:
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CAUTION: In the configuration, make sure that the IGMP general query interval is
larger than the maximum response time for IGMP general queries. Otherwise,
multicast group members may be deleted by mistake.
Configuring Source IP
Address of IGMP Queries
Upon receiving an IGMP query whose source IP address is 0.0.0.0 on a port, the
switch will not set that port as a router port. This may prevent multicast
forwarding entries from being correctly created at the data link layer and cause
multicast traffic forwarding failure in the end. When a Layer 2 device acts as an
IGMP-Snooping querier, to avoid the aforesaid problem, you are commended to
configure a non-all-zero IP address as the source IP address of IGMP queries.
Follow these steps to configure source IP address of IGMP queries:
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CAUTION: The source address of IGMP query messages may affect IGMP querier
selection within the segment.
Configuring an IGMP
Snooping Policy
Configuration
Prerequisites
Before configuring an IGMP Snooping policy, complete the following task:
■ Enable IGMP Snooping in the VLAN or enable IGMP on the desired VLAN
interface
To do… Use the command… Remarks
Enter system view system-view -
Enter VLAN view vlan vlan-id -
Configure IGMP general
query interval
igmp-snooping
query-interval interval
Optional
60 seconds by default
Configure the maximum
response time to IGMP
general queries
igmp-snooping
max-response-time interval
Optional
10 seconds by default
Configure the IGMP
last-member query interval
igmp-snooping
last-member-query-interval
interval
Optional
1 second by default
To do… Use the command… Remarks
Enter system view system-view -
Enter VLAN view vlan vlan-id -
Configure the source address
of IGMP general queries
igmp-snooping
general-query source-ip
{ current-interface |
ip-address }
Optional
0.0.0.0 by default
Configure the source IP
address of IGMP
group-specific queries
igmp-snooping
special-query source-ip
{ current-interface |
ip-address }
Optional
0.0.0.0 by default