R3303-HP HSR6800 Routers IP Multicast Configuration Guide

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Analysis
• The ACL rule is incorrectly configured.
• The multicast group policy is not correctly applied.
• The function of dropping unknown multicast data is not enabled, so unknown multicast data is
flooded.
Solution
1. Use the display acl command to check the configured ACL rule. Make sure the ACL rule conforms
to the multicast group policy to be implemented.
2. Use the display this command in IGMP-snooping view or in the corresponding interface view to
verify that the correct multicast group policy has been applied. If not, use the group-policy or
igmp-snooping group-policy command to apply the correct multicast group policy.
3. Use the display current-configuration command to verify that the function of dropping unknown
multicast data is enabled. If not, use the drop-unknown or igmp-snooping drop-unknown
command to enable the function of dropping unknown multicast data.
Appendix
Processing of multicast protocol messages
When a router is enabled with Layer 3 multicast routing and IGMP snooping, and is installed with the
SAP module, it processes multicast protocol messages differently under different conditions, as follows:
• If only IGMP is enabled on the router, or if both IGMP and PIM are enabled on this router, the router
does the following:
{ Maintains dynamic member ports or dynamic router ports according to IGMP packets
{ Maintains dynamic router ports according to PIM hello packets
• If only PIM is enabled on the router, the following occur:
{ The router broadcasts IGMP messages as unknown messages in the VLAN.
{ After receiving a PIM hello message, the router maintains the corresponding dynamic router
port.
• If IGMP is disabled on the router, one of the following occurs:
{ If PIM is disabled, the router deletes all its dynamic member ports and dynamic router ports.
{ If PIM is enabled, the router deletes only its dynamic member ports but not its dynamic router
ports.
NOTE:
On a router with Layer-3 multicast routing enabled and installed with the SAP module, use the display
igmp group port-info command to view Layer-2 port information.
• If PIM is disabled on the router, one of the following occurs:
{ If IGMP is disabled, the router deletes all its dynamic router ports.
{ If IGMP is enabled, the router maintains all its dynamic member ports and dynamic router ports.