36Step Command Remarks3. Set the maximum number ofmulticast groups that a portcan join.igmp-snooping group-limit limit[ vlan vlan-list ]By default, the upper limit is 2000for the S5500-EI switches, and1000 for the S5500-SI switches.Enabling multicast group replacementFor various reasons, the number of multicast groups that the switch or a port joins might exceed the upperlimit. In addition, in some specific applications, a multicast group that the switch newly joins must replacean 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 switch oron a certain port. When the number of multicast groups that the switch or on the port has joined reachesthe limit, one of the following occurs:• If the multicast group replacement feature is disabled, new IGMP reports are automaticallydiscarded.• If the multicast group replacement feature is enabled, the multicast group that the switch or a portnewly joins automatically replaces an existing multicast group that has the lowest address.IMPORTANT:In the configuration, be sure to configure the maximum number of multicast groups allowed on a port (see"Setting the maximum number of multicast groups that a port can join") before enabling multicast groupreplacement. Otherwise, the multicast group replacement functionality will not take effect.Enabling multicast group replacement globallyStep Command Remarks1. Enter system view. system-view N/A2. Enter IGMP-snooping view. igmp-snooping N/A3. Enable multicast groupreplacement. overflow-replace [ vlan vlan-list ] Disabled by defaultEnabling multicast group replacement on a portStep Command Remarks1. Enter system view. system-view N/A
