sorry for delay! R2___ ___ > R5 R4 R2' configuration interface Serial1/1 ip address 1.1.1.2 255.255.255.0 ip pim sparse-mode encapsulation frame-relay ip ospf network non-broadcast ip ospf hello-interval 5 ip ospf dead-interval 15 ip ospf priority 0 serial restart-delay 0 frame-relay map ip 1.1.1.4 205 frame-relay map ip 1.1.1.5 205 broadcast no frame-relay inverse-arp ! router ospf 1 net 0.0.0.0 0.0.0.0 a 0 show ip pim rp mapping PIM Group-to-RP Mappings Group(s) 224.0.0.0/4 RP 10.5.5.5 (?), v2v1 Info source: 10.5.5.5 (?), elected via Auto-RP Uptime: 00:01:41, expires: 00:00:28 show ip mroute IP Multicast Routing Table Flags: D - Dense, S - Sparse, B - Bidir Group, s - SSM Group, C - Connected, L - Local, P - Pruned, R - RP-bit set, F - Register flag, T - SPT-bit set, J - Join SPT, M - MSDP created entry, X - Proxy Join Timer Running, A - Candidate for MSDP Advertisement, U - URD, I - Received Source Specific Host Report, Z - Multicast Tunnel, z - MDT-data group sender, Y - Joined MDT-data group, y - Sending to MDT-data group Outgoing interface flags: H - Hardware switched, A - Assert winner Timers: Uptime/Expires Interface state: Interface, Next-Hop or VCD, State/Mode (*, 224.0.1.39), 00:00:02/stopped, RP 0.0.0.0, flags: DP Incoming interface: Null, RPF nbr 0.0.0.0 Outgoing interface list: Null (10.5.5.5, 224.0.1.39), 00:00:02/00:02:57, flags: PT Incoming interface: Serial1/1, RPF nbr 1.1.1.5 Outgoing interface list: Null (*, 224.0.1.40), 00:00:09/stopped, RP 0.0.0.0, flags: DPL Incoming interface: Null, RPF nbr 0.0.0.0 Outgoing interface list: Null (10.5.5.5, 224.0.1.40), 00:00:04/00:02:55, flags: PLT Incoming interface: Serial1/1, RPF nbr 1.1.1.5 Outgoing interface list: Null R5' configuration interface Serial1/0 ip address 1.1.1.5 255.255.255.0 ip pim nbma-mode ip pim sparse-mode encapsulation frame-relay ip ospf network non-broadcast ip ospf hello-interval 5 ip ospf dead-interval 15 serial restart-delay 0 frame-relay map ip 1.1.1.2 502 broadcast frame-relay map ip 1.1.1.4 504 broadcast no frame-relay inverse-arp ! interface Loopback0 ip address 10.5.5.5 255.255.255.0 ip pim sparse-mode ip ospf network point-to-point ! router ospf 1 network 0.0.0.0 0.0.0.0 a 0 neighbor 1.1.1.2 neighbor 1.1.1.4 ! ip pim send-rp-announce Loopback0 scope 15 interval 10 ip pim send-rp-discovery Loopback0 scope 15 interval 10 show ip pim rp mapping PIM Group-to-RP Mappings This system is an RP (Auto-RP) This system is an RP-mapping agent (Loopback0) Group(s) 224.0.0.0/4 RP 10.5.5.5 (?), v2v1 Info source: 10.5.5.5 (?), elected via Auto-RP Uptime: 00:22:12, expires: 00:00:21 show ip mroute IP Multicast Routing Table Flags: D - Dense, S - Sparse, B - Bidir Group, s - SSM Group, C - Connected, L - Local, P - Pruned, R - RP-bit set, F - Register flag, T - SPT-bit set, J - Join SPT, M - MSDP created entry, X - Proxy Join Timer Running, A - Candidate for MSDP Advertisement, U - URD, I - Received Source Specific Host Report, Z - Multicast Tunnel, z - MDT-data group sender, Y - Joined MDT-data group, y - Sending to MDT-data group Outgoing interface flags: H - Hardware switched, A - Assert winner Timers: Uptime/Expires Interface state: Interface, Next-Hop or VCD, State/Mode (*, 239.1.1.1), 00:00:06/00:03:23, RP 10.5.5.5, flags: S Incoming interface: Null, RPF nbr 0.0.0.0 Outgoing interface list: Serial1/0, 1.1.1.4, Forward/Sparse, 00:00:06/00:03:23 (*, 224.0.1.39), 00:00:37/stopped, RP 0.0.0.0, flags: DCL Incoming interface: Null, RPF nbr 0.0.0.0 Outgoing interface list: Serial1/0, 224.0.1.39, Forward/Sparse, 00:00:37/00:02:22 Loopback0, Forward/Sparse, 00:00:37/00:02:44 (10.5.5.5, 224.0.1.39), 00:00:30/00:02:50, flags: LT Incoming interface: Loopback0, RPF nbr 0.0.0.0 Outgoing interface list: Serial1/0, 224.0.1.39, Forward/Sparse, 00:00:30/00:02:30 (*, 224.0.1.40), 00:00:37/stopped, RP 0.0.0.0, flags: DCL Incoming interface: Null, RPF nbr 0.0.0.0 Outgoing interface list: Serial1/0, 224.0.1.40, Forward/Sparse, 00:00:39/00:02:20 Loopback0, Forward/Sparse, 00:00:39/00:02:39 (10.5.5.5, 224.0.1.40), 00:00:35/00:02:54, flags: LT Incoming interface: Loopback0, RPF nbr 0.0.0.0 Outgoing interface list: Serial1/0, 224.0.1.40, Forward/Sparse, 00:00:35/00:02:24 R4's configuration interface Serial1/0 ip address 1.1.1.4 255.255.255.0 ip pim sparse-mode encapsulation frame-relay ip ospf network non-broadcast ip ospf hello-interval 5 ip ospf dead-interval 15 ip ospf priority 0 serial restart-delay 0 frame-relay map ip 1.1.1.2 405 frame-relay map ip 1.1.1.5 405 broadcast no frame-relay inverse-arp ! interface Ethernet0/0 ip address 2.2.2.4 255.255.255.0 ip pim sparse-mode ip igmp join-group 239.1.1.1 half-duplex ! router ospf 1 net 0.0.0.0 0.0.0.0 a 0 show ip pim rp mapping PIM Group-to-RP Mappings Group(s) 224.0.0.0/4 RP 10.5.5.5 (?), v2v1 Info source: 10.5.5.5 (?), elected via Auto-RP Uptime: 00:07:02, expires: 00:00:28 show ip mroute IP Multicast Routing Table Flags: D - Dense, S - Sparse, B - Bidir Group, s - SSM Group, C - Connected, L - Local, P - Pruned, R - RP-bit set, F - Register flag, T - SPT-bit set, J - Join SPT, M - MSDP created entry, X - Proxy Join Timer Running, A - Candidate for MSDP Advertisement, U - URD, I - Received Source Specific Host Report, Z - Multicast Tunnel, z - MDT-data group sender, Y - Joined MDT-data group, y - Sending to MDT-data group Outgoing interface flags: H - Hardware switched, A - Assert winner Timers: Uptime/Expires Interface state: Interface, Next-Hop or VCD, State/Mode (*, 239.1.1.1), 00:16:40/00:02:13, RP 10.5.5.5, flags: SCL Incoming interface: Serial1/0, RPF nbr 1.1.1.5 Outgoing interface list: Ethernet0/0, Forward/Sparse, 00:01:59/00:02:13 (*, 224.0.1.39), 00:16:37/stopped, RP 0.0.0.0, flags: DP Incoming interface: Null, RPF nbr 0.0.0.0 Outgoing interface list: Null (10.5.5.5, 224.0.1.39), 00:00:45/00:02:14, flags: PT Incoming interface: Serial1/0, RPF nbr 1.1.1.5 Outgoing interface list: Null (*, 224.0.1.40), 00:16:40/stopped, RP 0.0.0.0, flags: DPL Incoming interface: Null, RPF nbr 0.0.0.0 Outgoing interface list: Null (10.5.5.5, 224.0.1.40), 00:16:38/00:02:55, flags: PLT Incoming interface: Serial1/0, RPF nbr 1.1.1.5 Outgoing interface list: Null Now when i started ping from R2 to R4 here is the results:- On R2 Rack1R2#ping 239.1.1.1 repeat 100 Type escape sequence to abort. Sending 100, 100-byte ICMP Echos to 239.1.1.1, timeout is 2 seconds: Reply to request 0 from 1.1.1.4, 232 ms......................................... ............................ ........................ Reply to request 94 from 1.1.1.4, 244 ms..... On R5 Rack2R5#show ip mroute 239.1.1.1 IP Multicast Routing Table Flags: D - Dense, S - Sparse, B - Bidir Group, s - SSM Group, C - Connected, L - Local, P - Pruned, R - RP-bit set, F - Register flag, T - SPT-bit set, J - Join SPT, M - MSDP created entry, X - Proxy Join Timer Running, A - Candidate for MSDP Advertisement, U - URD, I - Received Source Specific Host Report, Z - Multicast Tunnel, z - MDT-data group sender, Y - Joined MDT-data group, y - Sending to MDT-data group Outgoing interface flags: H - Hardware switched, A - Assert winner Timers: Uptime/Expires Interface state: Interface, Next-Hop or VCD, State/Mode (*, 239.1.1.1), 00:03:27/00:03:20, RP 10.5.5.5, flags: S Incoming interface: Null, RPF nbr 0.0.0.0 Outgoing interface list: Serial1/0, 1.1.1.4, Forward/Sparse, 00:03:27/00:03:20 (1.1.1.2, 239.1.1.1), 00:00:37/00:02:59, flags: PT Incoming interface: Serial1/0, RPF nbr 0.0.0.0 Outgoing interface list: Null on R4 Rack2R4#show ip mroute 239.1.1.1 IP Multicast Routing Table Flags: D - Dense, S - Sparse, B - Bidir Group, s - SSM Group, C - Connected, L - Local, P - Pruned, R - RP-bit set, F - Register flag, T - SPT-bit set, J - Join SPT, M - MSDP created entry, X - Proxy Join Timer Running, A - Candidate for MSDP Advertisement, U - URD, I - Received Source Specific Host Report, Z - Multicast Tunnel, z - MDT-data group sender, Y - Joined MDT-data group, y - Sending to MDT-data group Outgoing interface flags: H - Hardware switched, A - Assert winner Timers: Uptime/Expires Interface state: Interface, Next-Hop or VCD, State/Mode (*, 239.1.1.1), 00:18:53/stopped, RP 10.5.5.5, flags: SCL Incoming interface: Serial1/0, RPF nbr 1.1.1.5 Outgoing interface list: Ethernet0/0, Forward/Sparse, 00:04:12/00:02:00 (1.1.1.2, 239.1.1.1), 00:01:23/00:01:43, flags: LJT Incoming interface: Serial1/0, RPF nbr 0.0.0.0 Outgoing interface list: Ethernet0/0, Forward/Sparse, 00:01:23/00:02:00 For ur convenience paste all in ur note pad, it will be much clear to u !! According to me as i mentioned in the previous post that the problem is when the client tries to convert the traffic from Shared tree to SPT and it sends prune to R5 because R4 thinks that it has another shortest path which is actually via R5! One another point i changed the network type to Point-to-multipoint! it works ! Because if we look at the routing table of R4 Rack2R4#show ip route ospf 1.0.0.0/8 is variably subnetted, 3 subnets, 2 masks O 1.1.1.2/32 [110/128] via 1.1.1.5, 00:06:19, Serial1/0 O 1.1.1.5/32 [110/64] via 1.1.1.5, 00:06:19, Serial1/0 10.0.0.0/24 is subnetted, 1 subnets O 10.5.5.0 [110/65] via 1.1.1.5, 00:06:19, Serial1/0 R2 is reachable via R5 according to its routing table! So thats why it is not sending the prune message to R5 . Now look at the routing table of R4 with network type non-broadcast Rack2R4#show ip route Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2 i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2 ia - IS-IS inter area, * - candidate default, U - per-user static route o - ODR, P - periodic downloaded static route Gateway of last resort is not set 1.0.0.0/24 is subnetted, 1 subnets C 1.1.1.0 is directly connected, Serial1/0 2.0.0.0/24 is subnetted, 1 subnets C 2.2.2.0 is directly connected, Ethernet0/0 10.0.0.0/24 is subnetted, 1 subnets O 10.5.5.0 [110/65] via 1.1.1.5, 00:00:44, Serial1/0 Now, here R2 is reachable via serial1/0 which is a multi-access non-broadcast network, so the router R4 thinks that it can reach directly to R2 and it sends prune to R5 . Now , i still have one confusion , if this is the case ( which i explained above ) then it should be solved if i configure ip pim spt-threshold infinity on R4 which means that it should not join SPT . ( in non-broadcast network ) But i am facing the same problem even after configuring this on R4.