R2#sh run | b interface Tun
interface Tunnel0
 ip address 24.24.24.2 255.255.255.0
 ip pim sparse-dense-mode
 tunnel source 2.2.2.2
 tunnel destination 4.4.4.4
!
R4#Sh run | b interface Tun
interface Tunnel0
 ip address 24.24.24.4 255.255.255.0
 ip pim sparse-dense-mode
 ip igmp join-group 224.44.44.44
 tunnel source Loopback0
 tunnel destination 2.2.2.2
!
!


R4(config)#do sh run | i ip mroute
ip mroute 0.0.0.0 0.0.0.0 Tunnel0