R3303-HP HSR6800 Routers IP Multicast Configuration Guide

31
When you configure this maximum number, if the number of multicast groups the port has joined exceeds
the configured maximum value, the system deletes all the forwarding entries for the port. The hosts
connected to the port can join multicast groups before the number of multicast groups that the port joins
reaches the maximum value. When the port joins a multicast group, one of the following might occur:
• If the port has been configured as a static member port for a multicast group, the system
immediately establishes a forwarding entry for the static member port.
• If the port has been configured as a simulated member port, the system establishes a forwarding
entry after receiving a report from the simulated member host.
To set the maximum number of multicast groups that a port can join:
Step Command Remarks
1. Enter system view.
system-view N/A
2. Enter Layer 2 Ethernet
interface view or Layer 2
aggregate interface view, or
enter port group view.
• Enter Layer 2 Ethernet interface
view or Layer 2 aggregate
interface view:
interface interface-type
interface-number
• Enter port group view:
port-group manual
port-group-name
Use either command.
3. Set the maximum number of
multicast groups that the port
can join.
igmp-snooping group-limit limit
[ vlan vlan-list ]
The default value is 1000.
Enabling multicast group replacement
For various reasons, the number of multicast groups that the router or a port joins might exceed the upper
limit. In addition, in some specific applications, a multicast group that the router newly joins must replace
an existing multicast group automatically. A typical example is channel switching. To view a new channel,
a user switches from the current multicast group to the new one.
To realize such requirements, you can enable the multicast group replacement function on the router or
on a certain port. When the number of multicast groups that the router or on the port has joined reaches
the limit, one of the following occurs:
• If the multicast group replacement feature is disabled, new IGMP reports are automatically
discarded.
• If the multicast group replacement feature is enabled, the multicast group that the router or the port
newly joins automatically replaces an existing multicast group that has the lowest address.
IMPORTANT:
Be sure to configure the maximum number of multicast groups that a port can join to a value other than the
default one (see "Setting the maximum number of multicast grou
ps that a port can join") before enablin
g
multicast group replacement. Otherwise, the multicast
g
roup replacement functionality will not take effect.
Enabling multicast group replacement globally