152
Feature MSR900
MSR93X MSR20
-1X
MSR
20
MSR30 MSR50
MSR1000
Enabling
dropping
unknown
multicast
data in a
VLAN.
No. No. No.
No.
Supported by the
MSR30-11E or
MSR30-11F with
fixed switching
interfaces.
Not supported by
the MIM and XMIM
modules.
Supported by
the FIC
modules.
No
NOTE:
If you enable the function of dropping unknown multicast packets in the VLAN on an MSR installed with
the subcard MIM-16FSW, DMIM-24FSW, FIC-16FSW, or DFIC-24FSW, VLAN interfaces cannot be
configured to join the bridge group.
Configuration guidelines
•
For a device that supports both
drop-unknown
and
igmp-snooping drop-unknown
commands, do
not configure them at the same time. If you enable this function in IGMP-snooping view, you should
not enable or disable it in VLAN view, or vice versa.
•
If you enable the function of dropping unknown IPv4 multicast packets, unknown IPv6 multicast data
are automatically dropped.
Enabling dropping unknown multicast data globally
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Enter IGMP-snooping view.
igmp-snooping
N/A
3.
Enable dropping unknown
multicast data globally.
drop-unknown
Disabled by default.
Enabling dropping unknown multicast data in a VLAN
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Enter VLAN view.
vlan
vlan-id
N/A
3.
Enable dropping unknown
multicast data.
igmp-snooping drop-unknown
Disabled by default.
Enabling IGMP report suppression
When a Layer 2 switch receives an IGMP report from a multicast group member, the switch forwards the
message to the Layer 3 device that directly connects to the Layer 2 switch. When multiple members of a
multicast group are attached to the Layer 2 switch, the Layer 3 device might receive duplicate IGMP
reports for the multicast group from these members.
With the IGMP report suppression function enabled, within each query interval, the Layer 2 switch
forwards only the first IGMP report for the multicast group to the Layer 3 device. It does not forward the
