How does an S series switch take an action when the number of Layer 2 multicast entries exceed the limit

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Q: How does an S series switch process excess users after the number of users exceeds the value of group-limit?
A: If the number of dynamic users has exceeded the upper limit specified by group-limit, new users cannot go online, and the device does not disconnect the excess users.

Other related questions:
Layer 2 multicast entries and usage of S series switches
For an S series switch, entries fall into protocol and forwarding entries. Protocol entries include router port entries and host port entries. You can run the display igmp-snooping router-port command to check router port entries, run the display igmp-snooping port-info command to check host port entries, and run the display l2-multicast forwarding-table command to check forwarding entries. Protocol entries are triggered by protocol packets or manually generated. They are used to identify the protocol exchange status. Forwarding entries are generated based on protocol entries and are used to guide subsequent multicast data forwarding.

How does an S series switch age Layer 3 multicast entries
PIM deletes a Layer 3 multicast entry when the following conditions are met: - No traffic matches the entry. The multicast FIB management module counts packets matching each Layer 3 multicast entry. If no packet matches an entry within 210 seconds, the multicast FIB management module sends an entry inactive message to the PIM module. - The outbound interface list of the entry does not contain any outbound interface learned from PIM Join messages or PIM Prune messages. The outbound interfaces learned from IGMP on the designated router (DR) do not affect aging of Layer 3 multicast entries. If all the preceding conditions are met, PIM considers the entry invalid and deletes it.

Why does an S series switch generates Layer 2 multicast forwarding entries in only one VLAN
After an S series switch receives Report messages from the same multicast group in different VLANs, Layer 2 multicast entries are generated in only the VLAN where Report messages are generated first. The causes are as follows: An S5700SI switch running a version earlier than V200R005 or an S5710-C-LI does not generate the same multicast forwarding entry for a multicast group in multiple VLANs. That is, a multicast group can have a forwarding entry only in one VLAN. To solve this problem, configure a multicast VLAN so that multicast data can be distributed to user VLANs through the multicast VLAN. - The preceding restriction does not apply to the S5700SI, S5710-X-LI, S5700S-28X-LI-AC, S5700S-52X-LI-AC, S5720S-SI, S5720SI, and E600 running V200R005 and later versions. These switches, however, cannot generate the same multicast forwarding entry for a multicast group in multiple multicast VLANs. That is, a multicast group can have a forwarding entry only in one multicast VLAN. - The S2700 does not allow an interface to function as the outbound interface of the same multicast forwarding entry in multiple VLAN. That is, one interface can function as the outbound interface of a multicast group in only one VLAN. To solve this problem, add each interface to only one VLAN so that a multicast group has different outbound interfaces in different VLANs.

How is convergence performance of Layer 2 multicast accelerated on an S series switch?
When the network topology changes, Layer 2 multicast detects the topology change by responding to notification messages of ring network protocols. Layer 2 multicast sends General Query messages in the VLAN where the topology changes to re-collect group member relationships. Ring network protocols include STP, MSTP, RRPP, Smart Link, and SEP. The ring network protocols supported by the switches excluding the S1700 are as follows: - STP: supported by all switch models - MSTP: supported by all switch models excluding the S2700SI - RRPP: supported by all switch models excluding the S1720 and S2700SI - Smart Link: supported by all switch models excluding the S1720, S2700SI, S2710SI, and S2700EI - SEP: supported by all switch models excluding the S1720, S2700SI, S2710SI, and S2700EI

How does an S series switch process packets when Layer 2 multicast references an ACL
In Layer 2 multicast, three functions need to reference the ACL. After an ACL is referenced, packets are processed based on ACL rules. If no rule is configured, packets are processed as follows: - IGMP snooping group policy: In V200R001 and earlier versions, the default rule is permit. In V200R002 and later versions, if default-permit is not configured, the default rule is deny; if default-permit is configured, the default rule is permit. - IGMP snooping prompt leave: In V200R001 and earlier versions, the default rule is permit. In V200R002 and later versions, if default-permit is not configured, the default rule is deny; if default-permit is configured, the default rule is permit. - IGMP snooping SSM policy: The default rule is deny.

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