I've been noticing for a while now that there has been this message popping up in the logs of one of my routers, exactly once a minute stating the error:
%IGMP-4-NO_INPUT: VRF xx: IGMP packet without input interface received from 18.104.22.168 for 22.214.171.124 -Process= "IGMP Input"
where the recieved address is the tunnel address of the dmvpn tunnel that we use to connect to remote sites.
Multicast is not one of my strong suits and I haven't been able to find much material online relating to this specific area, anyone have any ideas what kinds of things could produce an error like this consistently?
The 126.96.36.199 IP is the all-hosts group multicast. So something is trying to start a multicast message. A few questions:
Your right that there isn't much information out there on that specific error code (that is helpful anyways). I would suggest looking at the other information in the logs to help direct you to another troubleshooting step.
do you have "ip multicast routing" enabled?
are you using "ip pim sparse-dense mode"
what does "show ip igmp snooping" give you?
show ip mroute summary
Debugs you could try - just not all at once :D
debug ip mroute
debug ip igmp
debug ip pim
debug ip mpacket
1. Yes we do have a tunnel VRF configured on that tunnel, the same one that's specified on that log input.
2. The IP in the message is the IP on that tunnel interface on this router, which acts as the hub for our DMVPN network, which we use a private IP range for the subnet.
We do have multicast routing enabled, and we don't have sparse-dense mode enabled, rather just sparse mode.
For the IGMP snooping command, I'm getting the same output for all of my VLAN's of
IGMP snooping : Enabled
IGMPv2 immediate leave : Disabled
Multicast router learning mode : pim-dvmrp
Last Member Query Interval : 1000
CGMP interoperability mode : IGMP_ONLY
I'm not sure how to read this so I don't know exactly what it's telling me, but it's the same for all of my VLAN's.