Whether S series switch can generate a multicast table item by IGMPv2 message when it specifies the source address of the programme group

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For S series switches, BTV has a similar configuration as follows:

multicast-group tv1 ip-address 232.0.0.1 source 10.1.1.1

After receiving the IGMP Report message, it is necessary to check the internal address and the source address of the packet. While the IGMPv2 message does not specify the source address, it will fail to generate a forwarding table entry when the check is performed.

Other related questions:
Whether the source address specified in the security policy is the translated address when the source NAT policy is configured
The source address specified in the security policy is the address before NAT when the source NAT policy is configured. When the firewall translates an address in a packet, it searches for the interzone security policy. The firewall translates only the address that passes the security policy check and matches the conditions defined in the interzone policy. Therefore, the source address specified in the interzone security policy is the address before NAT, that is, the private IP address.

Can an S series switches forward a packet if both the source and destination IP addresses of the packet are multicast addresses
The S5710-C-LI or S5700SI drops packets whose source and destination IP addresses are both multicast addresses. Other switches broadcast such packets in a VLAN.

Why does an S series switch fail to generate IGMP group membership entries when receiving IGMP packets
If an S series switch cannot generate entries, the possible causes are as follows: The version of received IGMP messages is later than the IGMP version configured on the switch. Solution: Run the display igmp interface interface-type interface-num command to check the IGMP version on the interface receiving the IGMP messages. If the IGMP version on the interface is earlier than the version of received IGMP messages, run the igmp version version command in the interface view to set a later IGMP version. The interface receives IGMPv1 or IGMPv2 messages with addresses in the SSM group address range, but SSM mapping is not configured on the switch. Solution: Check whether the group address in the received IGMP messages is in the SSM group address range. If so, run the igmp ssm-mapping enable command in the interface view to enable SSM mapping, and then run the ssm mapping group-address mask source-address command in the IGMP view to configure SSM mapping entries matching the IGMP messages. The group address in received IGMP packets is the reserved group address. The group addresses in the range of 224.0.0.1 to 224.0.0.255 are reserved for protocols. When receiving IGMP Report messages with destination addresses in this range, the switch does not generate IGMP group membership entries.

Why does an S series switch fail to generate Layer 3 multicast forwarding entries when receiving multicast data packets with destination IP addresses in the SSM group address range
An S series switch generates Layer 3 multicast forwarding entries for the group addresses in the SSM group address range only when receiving multicast protocol packets. Multicast data packets cannot trigger generation of Layer 3 multicast forwarding entries for such group addresses. Use either of the following methods to solve this problem: - Configure IGMPv3 or SSM mapping on user-side interfaces. When users order multicast programs, they can send IGMP messages with source-group information to trigger generation of Layer 3 multicast forwarding entries. - Configure PIM-SM on downstream devices. When users need to join a specified source-group, they can send PIM messages with source-group information to trigger generation of Layer 3 multicast forwarding entries.

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