ip igmp join-group

Does anyone know how to force an interface that is not running PIM to re-register when you use the command "ip igmp join-group"? It will send a register message one time then stop sending them so the group will be pruned off in 3 minutes.

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Comments

PStefanov

Are you sure the router doesn't send a register message once every 60 seconds? I am not sure how the router sends a register message at first place without PIM being enabled on the interface. I will lab this up and see what happens.

dtlokee

PIM != IGMP, you can still join a IGMP group without PIM, but it does not re-register within the 3 minute timer so it will eventually prune the tree.

mikeeo

Explain what you are trying to do.

PStefanov

dtlokee wrote:

PIM != IGMP, you can still join a IGMP group without PIM, but it does not re-register within the 3 minute timer so it will eventually prune the tree.

I meant that if PIM is not enabled on an interface and if you receive an IGMP membership report or register using this command on that same interface, PIM will not send a join message toward the RP.

Regarding you question, by "re-register" do you mean sending a join message, because the ip igmp join-group command makes the router send a join message?

Please clarify your question, becuase I am a bit confused

dtlokee

I am using old routers as hosts in the lab without multicast routing or ip routing enabled. When you use a ip igmp join-group command the will send a igmp join message one time but that's it, they will not respond to the group queries and therefore will get pruned. No big deal, just a bit annyoing needing to re-issue the commands every 3 minutes

networker050184

I know what you are talking about I was getting frustrated with this yesterday. Let us know if you figure it out.