NEC IP8800/S6700, IP8800/S6600 manual Multicast Data Is Double-relayed on IPv4 PIM-SM Network

3.Troubleshooting Functional Failures in Operation

No.	Troubleshooting Steps and Command	Action
4	Check to see if IGMP snooping is set to the port in which static	When IGMP snooping is set, confirm the following:
	group join function is working.	• Confirm that relay port is set as multicast port for IGMP
	show igmp-snooping	snooping
		• See "3.5.4 Multicast Relay by IGMP snooping Is
		Disabled."
5	Confirm that no interface in abnormal state is detected.	See notices and confirm that warning information is not
	show ip igmp interface	output. When warning information is output, check the
		following:
		• L: The number of join request exceeded the maximum
		number expected. Check to see the number of connected
		users.
		• Q: The IGMP version of neighboring router is different.
		Adjust it to the same IGMP version.
		• R: A user who transmitted reports unreceivable at the
		present settings exists. Change the IGMP version of this
		system or confirm the settings of the participant.
		• S: Some of the participant information are being discarded
		because the number of source exceeded the upper limit
		defined to store source per message in IGMPv3. Check the
		settings of the participant.

(5) first-hop-router check items

The table below shows the items to be checked when this system is the first-hop-router in the IPv4 PIM-SM network configuration.

Table 3-26: first-hop-router Check Items

No.	Troubleshooting Steps and Command	Action
1	Confirm that this system is directly connected to the multicast	If not, check the network configuration.
	sender.
2	Confirm that PIM or IGMP is running on the interface	If PIM or IGMP is not running, check the configuration and
	connected to the multicast sender.	set the configuration to run PIM or IGMP.
	show ip pim interface
	show ip igmp interface
3	Confirm that the multicast relay routing information exists.	If the multicast routing information does not exist, confirm
	show ip mroute	that multicast data source address is the network address of
		the interface directly connected to the multicast sender.

3.8.2Multicast Data Is Double-relayed on IPv4 PIM-SM Network

If multicast data is double-relayed in the IPv4 PIM-SM network configuration, check the settings of each router and set the configuration to run PIM on the interface for a network having multiple routers.

If double-relay still continues, check the following:

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