Enabling Dropping Unknown Multicast Data; Enabling Igmp Report Suppression - HP 6125XLG Ip Multicast Configuration Manual

Step
2. Enter Layer 2 Ethernet
interface view.
3. Enable multicast source port
filtering.

Enabling dropping unknown multicast data

Unknown multicast data refers to multicast data for which no forwarding entries exist in the IGMP
snooping forwarding table. When the switch receives such multicast data, one of the following occurs:
• If dropping unknown multicast data is disabled, the switch floods unknown multicast data in the
VLAN to which the data belongs.
If dropping unknown multicast data is enabled, the switch forwards unknown multicast data to other
•
router ports instead of flooding it in the VLAN. If no other router ports exist, the switch drops the
unknown multicast data.
To enable dropping unknown multicast data for a VLAN:
Step
1. Enter system view.
2. Enter VLAN view.
3. Enable dropping unknown
multicast data for the VLAN.

Enabling IGMP report suppression

After receiving an IGMP report from a multicast group member, a Layer 2 switch forwards the IGMP
report to the directly connected Layer 3 device. If multiple members of a multicast group are attached to
the Layer 2 switch, the Layer 3 device will receive multiple membership reports for the same multicast
group.
To reduce the multicast traffic, you can enable the IGMP report suppression function on the Layer 2 switch.
In this way, the Layer 2 switch forwards only the first IGMP report for the multicast group to the upstream
Layer 3 device during one query interval.
To enable IGMP report suppression:
Step
1. Enter system view.
2. Enter IGMP-snooping view.
3. Enable IGMP report
suppression.
Command
interface interface-type
interface-number
igmp-snooping source-deny
Command
system-view
vlan vlan-id
igmp-snooping drop-unknown
Command
system-view
igmp-snooping
report-aggregation
25
Remarks
N/A
By default, the multicast source port
filtering is disabled.
Remarks
N/A
N/A
By default, this function is disabled.
Unknown multicast data is flooded.
Remarks
N/A
N/A
By default, IGMP report suppression is
enabled.