Inconsistent memberships on routers on the same subnet
Symptom
Different memberships are maintained on different IGMP routers on the same subnet.
Analysis
A router running IGMP maintains multiple parameters for each interface, and these parameters
•
influence one another, forming very complicated relationships. Inconsistent IGMP interface
parameter configurations for routers on the same subnet will surely result in inconsistency of
memberships.
In addition, although an IGMP router is compatible with a host that is running a different version of
•
IGMP, all routers on the same subnet must run the same version of IGMP. Inconsistent IGMP versions
running on routers on the same subnet also leads to inconsistency of IGMP memberships.
Solution
Use the display current-configuration command to verify the IGMP configuration information on
1.
the interfaces.
Use the display igmp interface command on all routers on the same subnet to verify the
2.
IGMP-related timer settings. The settings should be consistent on all the routers.
Use the display igmp interface command to verify that all the routers on the same subnet are
3.
running the same version of IGMP.
101