Enabling Cisco Call Manager (6.1) Music on Hold (MOH) Multistreaming

Enable Multicast :

global switch/router commands (VRF)

ip multicast-routing
ip pim send-rp-announce Loopback0 scope 10

ip pim send-rp-discovery scope 10

ip multicast-routing vrf

ip pim vrf INTERNAL send-rp-announce scope 100 -- Best practice is Loopback rather than interface

ip pim vrf send-rp-discovery scope 100

Add ip pim sparse-dense-mode to all Interfaces that need to participate in the multicast stream or pass traffic

Show commands :

sh ip mroute
sh ip mroute vrf INTERNAL

Output :
*Snip*
(*, 239.1.1.1), 01:35:57/stopped, RP 10.2.70.253, flags: SP
Incoming interface: , RPF nbr 10.2.70.253, RPF-MFD
Outgoing interface list: Null
*Snip*


Call Manager Config :

Enable Multicast on MOH Audio Source
Enable Multicast on MOH Server - default IP is 239.1.1.1:16384
- enable increment port
Enable Multicast on Media Resource Group

NB//Enabling Multicast on the MRG requires endpoints to be reset to pick up the new settings, including gateways.