3Com Switch 4200G Configuration Guide

IGMP Snooping Configuration 253
Configuring Timers This configuration task is to manually configure the aging time of the router port, the
aging time of the multicast member ports, and the query response timeout time.
■ If the switch receives no general query message from a router within the aging
time of the router port, the switch removes the router port from the port member
lists of all MAC multicast groups.
■ If the Ethernet switch receives no IGMP report message within the maximum
query response time of a member port, it will remove the port from the multicast
group.
■ If the Ethernet switch receives no IGMP report message from a member port when
the query response time times out, it sends group-specific query to the port and
triggers the query response timer of the corresponding IP multicast group.
Enabling IGMP Fast
Leave Processing
Normally, when receiving an IGMP Leave message, IGMP Snooping does not
immediately remove the port from the multicast group, but sends a group-specific
query message. If no response is received in a given period, it then removes the port
from the multicast group.
If IGMP fast leave processing is enabled, when receiving an IGMP Leave message,
IGMP Snooping immediately removes the port from the multicast group. When a port
has only one user, enabling IGMP fast leave processing on the port can save
bandwidth.
Configuring IGMP
Snooping Filtering ACL
You can configure multicast filtering ACLs globally or on the switch ports connected
to user ends so as to use the IGMP Snooping filter function to limit the multicast
streams that the users can access. With this function, you can treat different VoD
users in different ways by allowing them to access the multicast streams in different
multicast groups.
Table 223 Configure timers
Operation Command Description
Enter system view system-view —
Configure the aging
time of the router port
igmp-snooping router-aging-time
seconds
Optional
By default, the aging
time of the router port is
105 seconds.
Configure the query
response timeout time
igmp-snooping max-response-time
seconds
Optional
By default, the query
response timeout time is
10 seconds.
Configure the aging
time of multicast
member ports
igmp-snooping host-aging-time seconds Optional
By default, the aging
time of multicast
member ports is 260
seconds.
Table 224 Enable the IGMP fast leave processing
Operation Command Description
Enter system view system-view —
Enter Ethernet port
view
interface interface-type interface-number —
Enable IGMP fast leave
processing
igmp-snooping fast-leave vlan vlan-id [
to vlan-id ]
Optional
By default this function is
disabled.