Dasan V8102, Руководство пользователя

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User Manual
UMN:CLI
V8102
499
Displaying Multicast Router Port
To display a current multicast router port for IGMP snooping, use the following command.
Command Mode Description
show ip igmp snooping mrouter
Enable
Global
Shows a current multicast router port for IGMP snoop-
ing globally.
show ip igmp snooping vlan
VLANS mrouter
Shows a current multicast router port for IGMP snoop-
ing on a specified VLAN.
VLANS: VLAN ID (1-4094)
10.2.3.8 TCN Multicast Flooding
When a network topology change occurs, the protocols for a link layer topology
– such as
spanning tree protocol (STP), Ethernet ring protection (ERP), etc
– notify switches in the
topology using a topology change notification (TCN).
When TCN is received, the switch where an IGMP snooping is running will flood multicast
traffic to all ports in a VLAN, since a network topology change in a VLAN may invalidate
previously learned IGMP snooping information. However, this flooding behavior is not de-
sirable if the switch has many ports that are subscribed to different groups. The traffic
could exceed the capacity of the link between the switch and the end host, resulting in
packet loss. Thus, a period of multicast flooding needs to be controlled to solve such a
problem.
Enabling TCN Multicast Flooding
To enable the switch to flood multicast traffic when TCN is received, use the following
command.
Command Mode Description
ip igmp snooping tcn flood
Global
Enables the switch to flood multicast traffic when TCN
is received.
ip igmp snooping tcn vlan
VLANS flood
Enables the switch to flood multicast traffic on a VLAN
when TCN is received.
VLANS: VLAN ID (1-4094)
To disable the switch to flood multicast traffic when TCN is received, use the following
command.
Command Mode Description
no ip igmp snooping tcn flood
Global
Disables the switch to flood multicast traffic when TCN
is received
no ip igmp snooping tcn vlan
VLANS flood