3Com 2928 - Baseline Plus Switch PWR, Руководство пользователя

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1-8
Table 1-4
Configuration items for advanced IGMP snooping features
Item Description
Port
Select the port on which advanced IGMP snooping features are to be configured.
The port can be an Ethernet port or Layer-2 aggregate port.
After a port is selected, advanced features configured on this port are displayed
at the lower part of this page.
Advanced IGMP snooping features configured on a Layer 2 aggregate port do
not interfere with features configured on its member ports, nor do they take part in
aggregation calculations; features configured on a member port of the aggregate
group will not take effect until it leaves the aggregate group
VLAN ID
Specify a VLAN in which you can configure the fast leave function for the port or
the maximum number of multicast groups allowed on the port.
Configurations made in a VLAN take effect for the ports in this VLAN only.
Group Limit
Configure the maximum number of multicast groups that the port can join.
With this feature, you can regulate multicast traffic on the port.
When the number of multicast groups a port has joined reaches the configured
threshold, the system deletes all the forwarding entries persistent on that port
from the IGMP snooping forwarding table, and the hosts on this port need to join
the multicast groups again.
Fast Leave
Enable or disable the fast leave function for the port.
With the fast leave function enabled on a port, the switch, when receiving an
IGMP leave message on the port, immediately deletes that port from the outgoing
port list of the corresponding forwarding table entry. Then, when receiving IGMP
group-specific queries for that multicast group, the switch will not forward them to
that port. In VLANs where only one host is attached to each port, the fast leave
function helps improve bandwidth and resource usage.
If fast leave is enabled for a port to which more than one host is attached, when
one host leaves a multicast group, the other hosts listening to the same multicast
group will fail to receive multicast data.
Return to
IGMP snooping configuration task list .
Display IGMP Snooping Multicast Entry Information
Select
Network
>
IGMP Snooping
in the navigation tree to enter the basic configuration page shown in
Figure 1-3 . Click the plus sign (+) in front of
Show Entries
to display information about IGMP snooping
multicast entries, as shown in Figure 1-6 . You can view the detailed information of an entry by click the
icon corresponding to the entry.
Figure 1-6
Display entry information