Multicast - Auto-rp filtering and multiple RPs

Overview

Configuring multiple RP can be beneficial to provide redundancy in the event of an RP failure. It is also possible to filter which RP's map to a group to provide a method to load balance multicast traffic across multiple RPs.
 
Concepts tested

• IP PIM Sparse dense mode configuration
• Configuring multiple RPs via auto RP
• Controlling groups mappings to RPs

Topology

Lab Tasks

• Assume R1 as the receiver and R4 as the source
• Configure multicast PIM on all paths appropriate for this lab
• Using Cisco's auto-rp configure both R2 and R3 as RPs with the following restrictions
• R4 should be the mapping agent
• R2 should be the RP and mapping agent for the group 224.0.0.0 /5
• R3 should be the RP and mapping agent for the group 232.0.0.0 /5
• The group 239.1.1.1 should use dense mode only
• Verify your configuration:
• R1 should join the group 224.0.10.10 which should use R2 as its RP
• R1 should join the group 232.0.10.10 which should use R3 as its RP
• R1 should join the group 239.1.1.1 which should be dense mode only
• R4 should ping each of these groups

GNS3 configuration file, requires IOS v15 for the 7200 router: Link


Solution

R1(config)#ip multicast-routing
R1(config)#int g0/0
R1(config-if)#ip pim sparse-dense-mode
R2(config)#ip multicast-routing
R2(config)#int lo 0
R2(config-if)#ip pim sparse-dense-mode
R2(config)#int g0/0
R2(config-if)#ip pim sparse-dense-mode
R2(config-if)#int g1/0
R2(config-if)#ip pim sparse-dense-mode
R2(config)#ip pim send-rp-discovery loopback 0 scope 10

R2(config)#ip access-list standard R2_GROUPS
R2(config-std-nacl)#deny 239.1.1.1
R2(config-std-nacl)#permit 224.0.0.0 7.255.255.255
R2(config)#ip pim send-rp-announce loopback 0 scope 10 group
R2(config)#ip pim send-rp-announce loopback 0 scope 10 group-list R2_GROUPS
R3(config)#ip multicast-routing
R3(config)#int loopback 0
R3(config-if)#ip pim sparse-dense-mode
R3(config-if)#int g0/0
R3(config-if)#ip pim sparse-dense-mode
R3(config-if)#int g1/0
R3(config-if)#ip pim sparse-dense-mode
R3(config)#ip access-list standard R3_GROUPS
R3(config-std-nacl)#deny 239.1.1.1
R3(config-std-nacl)#permit 232.0.0.0 7.255.255.255
R3(config)#ip pim send-rp-discovery loopback 0 scope 10
R3(config)#ip pim send-rp-announce loopback 0 scope 10 group-list R3_GROUPS
R4(config)#ip multicast-routing
R4(config)#int g0/0
R4(config-if)#ip pim sparse-dense-mode
R4(config-if)#int g1/0
R4(config-if)#ip pim sparse-dense-mode
R4(config-if)#int g2/0
R4(config-if)#ip pim sparse-dense-mode

R5(config)#ip multicast-routing
R5(config)#int g0/0
R5(config-if)#ip pim sparse-dense-mode


Verification

R5#ping 224.0.10.10 repeat 10
Type escape sequence to abort.
Sending 10, 100-byte ICMP Echos to 224.0.10.10, timeout is 2 seconds:
Reply to request 0 from 120.0.0.1, 192 ms
Reply to request 1 from 120.0.0.1, 124 ms
Reply to request 2 from 120.0.0.1, 92 ms
Reply to request 3 from 120.0.0.1, 124 ms


R1#sh ip mroute 224.0.10.10


(*, 224.0.10.10), 00:15:25/stopped, RP 2.2.2.2, flags: SJPL
  Incoming interface: GigabitEthernet0/0, RPF nbr 120.0.0.2
  Outgoing interface list: Null

(120.0.45.5, 224.0.10.10), 00:00:12/00:02:47, flags: PLT
  Incoming interface: GigabitEthernet0/0, RPF nbr 120.0.0.3
  Outgoing interface list: Null
R5#ping 232.0.10.10 repeat 10
Type escape sequence to abort.
Sending 10, 100-byte ICMP Echos to 232.0.10.10, timeout is 2 seconds:
Reply to request 0 from 120.0.0.1, 192 ms
Reply to request 0 from 120.0.0.1, 228 ms
Reply to request 1 from 120.0.0.1, 128 ms
Reply to request 2 from 120.0.0.1, 84 ms


R1#sh ip mroute 232.0.10.10


(*, 232.0.10.10), 00:16:44/stopped, RP 3.3.3.3, flags: SJPL
  Incoming interface: GigabitEthernet0/0, RPF nbr 120.0.0.3
  Outgoing interface list: Null

(120.0.45.5, 232.0.10.10), 00:00:07/00:02:52, flags: PLT
  Incoming interface: GigabitEthernet0/0, RPF nbr 120.0.0.3
  Outgoing interface list: Null
R5#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 120.0.0.1, 192 ms
Reply to request 0 from 120.0.0.1, 224 ms
Reply to request 1 from 120.0.0.1, 92 ms
Reply to request 2 from 120.0.0.1, 124 ms
Reply to request 3 from 120.0.0.1, 120 ms



R1#sh 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, E - Extranet,
       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,
       V - RD & Vector, v - Vector
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), 00:19:01/stopped, RP 0.0.0.0, flags: DCL
  Incoming interface: Null, RPF nbr 0.0.0.0
  Outgoing interface list:
    GigabitEthernet0/0, Forward/Sparse-Dense, 00:19:01/00:00:00

(120.0.45.5, 239.1.1.1), 00:00:31/00:02:28, flags: PLT
  Incoming interface: GigabitEthernet0/0, RPF nbr 120.0.0.3*
  Outgoing interface list: Null

R1#sh ip mroute 239.1.1.1 count
IP Multicast Statistics
11 routes using 3658 bytes of memory
5 groups, 1.20 average sources per group
Forwarding Counts: Pkt Count/Pkts per second/Avg Pkt Size/Kilobits per second
Other counts: Total/RPF failed/Other drops(OIF-null, rate-limit etc)
Group: 239.1.1.1, Source count: 1, Packets forwarded: 0, Packets received: 20
  Source: 120.0.45.5/32, Forwarding: 0/0/0/0, Other: 20/0/20

R2#deb ip pim auto-rp
PIM Auto-RP debugging is on
*Nov 25 08:40:38.359: Auto-RP(0): Build RP-Discovery packet
*Nov 25 08:40:38.359: Auto-RP(0):  Build mapping (224.0.0.0/5, RP:2.2.2.2), PIMv2 v1,
*Nov 25 08:40:38.363: Auto-RP(0):  Build mapping (232.0.0.0/5, RP:3.3.3.3), PIMv2 v1.
*Nov 25 08:40:38.367: Auto-RP(0):  Build mapping (-239.1.1.1/32, RP:3.3.3.3), PIMv2 v1.
R3#deb ip pim auto-rp
PIM Auto-RP debugging is on
*Nov 25 08:40:43.143: Auto-RP(0): Build RP-Discovery packet
*Nov 25 08:40:43.147: Auto-RP(0):  Build mapping (224.0.0.0/5, RP:2.2.2.2), PIMv2 v1,
*Nov 25 08:40:43.151: Auto-RP(0):  Build mapping (232.0.0.0/5, RP:3.3.3.3), PIMv2 v1.
*Nov 25 08:40:43.151: Auto-RP(0):  Build mapping (-239.1.1.1/32, RP:3.3.3.3), PIMv2 v1.