IGMP group interface state as "Stopped"--meaning and how to fix this

[Gongyuan Yao]

Hi,

We are trouble shooting a mcast problem. There are two routers are connected through a tunnel for mcast. The tunnel interface is up, but from sho ip igmp groups cmd, we see tunnel interface is in "stopped" state.

Can anyone please explain the reason for this? and give some advise for how to fix it.

Thanks in advance.

External-A#sho ip igmp groups
IGMP Connected Group Membership
Group Address    Interface                     Uptime    Expires   Last Reporter   Group Accounted
239.255.255.250  Port-channel89            16:18:34  00:02:24  130.14.89.32   
224.0.1.40       Tunnel0                          16:19:52  stopped   130.14.254.249 
224.0.1.40       Vlan8                             16:20:43  00:02:19  130.14.254.9  

[andrew.prince]

post the output of:-

show ip mroute

show ip mroute count

[Gongyuan Yao]

Thanks.

I have attached a log file for all of info from show cmds.

From show ip igmp group detail, we can see that interface tunnel0 is in Group Mode: INCLUDE, so the "stopped" status might be ok.

According to Cisco doc:

"The word "stopped" indicates that timing out of this entry is not determined by this expire timer. If the router is in INCLUDE mode for a group, then the whole group entry will time out after the last source entry has timed out (unless the mode is changed to EXCLUDE mode before it times out). "

So the stopped status might not indicate any problem.

Let me know what your suggestions and opinions.

Thanks.

gy

Intercon-rtr-A# sho ip igmp groups

IGMP Connected Group Membership

Group Address Interface Uptime Expires Last Reporter Group Accounted

224.0.1.40 Tunnel0 4d04h stopped 130.14.254.250

224.0.1.40 Vlan516 4d04h 00:02:28 130.14.254.18

Intercon-rtr-A# sho ip igmp groups detail

Flags: L - Local, U - User, SG - Static Group, VG - Virtual Group,

SS - Static Source, VS - Virtual Source,

Ac - Group accounted towards access control limit

Interface: Tunnel0

Group: 224.0.1.40

Flags: L U

Uptime: 4d04h

Group mode: INCLUDE

Last reporter: 130.14.254.250

Source list is empty

Interface: Vlan516

Group: 224.0.1.40

Flags: L U

Uptime: 4d04h

Group mode: EXCLUDE (Expires: 00:02:20)

Last reporter: 130.14.254.18

Source list is empty

Intercon-rtr-A#exit

[andrew.prince · Accepted solution]

What I am interested is why you are looking for IGMP host membership on a tunnel interface?  Strcitly speaking IGMP is used for Hosts talking to routers on the LAN @ layer 2.  Then the router will distribute that multicast join up the spared-tree.  A tunnel interface can be used for many things - but mainly for layer 3 routing.

How are you using your tunnel???

Really you should be usnig PIM over the tunnel.

[Gongyuan Yao]

Thanks.

The tunnel is used for multicast only through ASA as existing design. I believe the "stopped" status is not the problem.

It  is true that we are using PIM on the tunnel.

Thanks again for your time and help.

[andrew.prince]

OK no problem - so you need to know if the tunnel is behaving correctly, and send IGMP join.  Are you using RP's ??

post the output of:-

show ip pim interface

show ip pim neighbor

show ip mroute

show ip mroute count

[Gongyuan Yao]

Thanks for your help.

Pls see the attached file for simple network connections and logs. We have RP---it is in ext-router (router's loopback addr 130.14.91.200).

I can not see the mcast source for now, need to make some workaround to see it.

Anyway, if you see any problem, let me know.

I will be on vacation from tomorrow and back to office 10days later. Our ASA engineer is working on this issue. I will forward your suggestion to him.

This issue is involved two groups, both are not familiar with mcast.

Thank you again for your time and help.