53
for which this router is the Querier, to solicit membership information. On startup, a router
SHOULD send [Startup Query Count] General Queries spaced closely together [Startup Query
Interval] in order to quickly and reliably determine membership information. A General Query
is addressed to the all-systems multicast group (224.0.0.1), has a Group Address field of 0, and
has a Max Response Time of [Query Response Interval].
Port IGMP Querier Mode
Auto:
The Switch uses the port as an IGMP query port if the port receives IGMP query packets.
Fixed:
The Switch always treats the port(s) as IGMP query port(s). This is for when connecting an
IGMP multicast server to the port(s). The Switch always forwards the client’s
report/leave
packets to the port.
Normally, the port is connected to an IGMP server.
Edge:
The Switch does not use the port as an IGMP query port. The IGMP query packets received
by this port will be dropped.
Normally, the port is connected to an IGMP client.
Note:
The Switch will forward the IGMP join and leave packets to the query port.
Configurations:
Users can enable/disable the IGMP Snooping on the Switch. Users also can enable/disable the
IGMP Snooping on a specific VLAN. If the IGMP Snooping on the Switch is disabled, the IGMP
Snooping is disabled on all VLANs even some of the VLAN IGMP Snooping are enabled.
Default Settings
If received packets are not received after 400 seconds, all multicast entries will be deleted.
The default global IGMP snooping state is disabled.
The default VLAN IGMP snooping state is disabled for all VLANs.
The unknown multicast packets will be dropped.
The default port Immediate Leave state is disabled for all ports.
The default port Querier Mode state is auto for all ports.
The IGMP snooping Report Suppression is disabled.
Notices:
There are a global state and per VLAN states. When the global state is disabled, the
IGMP snooping on the Switch is disabled even per VLAN states are enabled. When the global
state is enabled, user must enable per VLAN states to enable the IGMP Snooping on the specific
VLAN.
6.2.1.2.
CLI Configuration
Node
Command
Description
enable
show igmp-snooping
This command displays the current IGMP snooping
configurations.