Migrate from multicast PIM SPARSE-DENSE to SPARSE Mode?

[SIMMN]

Say I have a environment runs PIM SPARSE-DENSE mode currently with

autoRP configured

(but no router has ip pim autorp listener configured). I need to add new L3 device into this environment and replace the existing RP router. But the challenge is that the new L3 device can only do PIM SPARSE mode...So I need to migrate existing PIM Sparse-dense mode to sparse mode in order to put in the new L3 device as the new RP, right?  

If so, do I just need to add

ip pim autorp listener

on all the PIM routers? Or I would have to manually add

ip pim autorp listener

as well as change

ip pim sparse-dense-mode to ip pim sparse-mode

for every PIM routers' interfaces?

[johnd2310]

Hi, 

You need the

ip pim autorp listener

on the device operating in pim sparse mode. In your case, this will be on the 'new L3 device'

https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipmulti_pim/configuration/xe-16-5/imc-pim-xe-16-5-book/imc-basic-cfg.html

Thanks

John

[SIMMN]

Thanks for the info but maybe I was not clear in the post. I would need to use the new L3 device to replace the current RP...

I will have

ip pim send-rp-announce and ip pim send-rp-discovery configured

on the new L3 device with all the interface as sparse-mode. I do think I need to have all the remaining PIM routers added with

ip pim autorp listener

as their interfaces are all in sparse-dense mode. But just not sure if this would actually work...

[johnd2310 · Accepted solution]

Hi

 ip pim autorp listener

is required if you have interfaces  running

 ip pim sparse-mode

. In your case you need it on the new L3 device. Your other devices are running interfaces in sparse-dense mode and do not need

ip pim autorp listener.

If you would like to migrate the other devices to pim sparse mode, then you will need to add the

ip pim autorp listener

on all the other devices.

Thanks

John

[SIMMN]

So my understanding of the

ip pim autorp listener

function might be wrong...I thought that command is only for the non-RP pim routers in a sparse-mode multi-cast environment. I guess it is actually for all the PIM routers if they are only running sparse-mode in the network, right? 

[johnd2310]

Hi,

Yes, you will only need it when you have interfaces running pim sparse-mode.

Thanks

John

[paul driver]

Hello
If sparse-dense mode isnt applicable then you can just statically apply a RP maping to each rtr and you should be good to go.

ip pim rp-address x.x.x.x