Interval
Function
immediate-leave
This command is used when
an interface connects to a
single host or to an IGMP
snooping switch. It minimizes
last member queries by
allowing the router to remove
the interface from a group
immediately after the
interface receives a leave
message for that group.
Default
Troubleshooting Multicast Stub Routing
and IGMP
This section gives strategies for troubleshooting multicast support on the stub
router only. If you determine that a problem originates on one of the remote
routers running the multicast routing protocol, then you must troubleshoot
that router and protocol. (See Chapter 11: Configuring Multicast Support
with PIM-SM.)
This section also describes how to troubleshoot IGMP, which is used both by
routers that run PIM-SM and those that run IGMP proxy.
Strategies and Tools
When hosts are not receiving multicast messages as they should, you need to
ascertain where the multicast messages are being lost.
Is the router receiving messages, but not forwarding them? In this case, the
router may not believe that the group exists on a network on which it does
exist, and IGMP functions might be at fault.
Is the router not receiving multicast messages at all? In this case, IGMP proxy
may be to blame; the helper device is not receiving reports from the router
telling it to send those multicast messages.
If you cannot locate the problem on the local router, you should, if possible,
troubleshoot the next-hop upstream router. See Chapter 11: Configuring
Multicast Support with PIM-SM for tips on troubleshooting PIM-SM.
Configuring Multicast Support for a Stub Network
Troubleshooting Multicast Stub Routing and IGMP
Range
—
Command Syntax
ip igmp immediate-
leave
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