Lab 157 - PIM Bootstrap Router

Prerequisites: CCNP level skills.

Personal Note!
Finding things out is a real pleasure ... Time to continue to get the buzz before all these memories drown in oblivion ...

Topology

Pic. 1 - Topology Diagram.

Note!
Routers and switches are already configured as per the topology diagram. All devices use OSPF area 0 as their routing protocol.

Task 1

Enable PIM Sparse mode on the following interfaces:

• R1 - Fa0/0
• R1 - S0/0.125
• R2 - Fa0/0
• R2 - Fa0/1
• R2 - S0/0
• R4 - Fa0/0
• R5 - Fa0/0
• R5 - S0/0

Task 2
Configure R2 to be BSR and R5 to be RP. Use the most stable interface on R2 and R5 to accomplish the task.


Task 3
Use R4 to simulate multicast server sending packets to 224.46.46.46. Users on VLAN 26 should receive this multicast feed. Verify your solution.

Solution

Task 1

Enable PIM Sparse mode on the following interfaces:

• R1 - Fa0/0
• R1 - S0/0.125
• R2 - Fa0/0
• R2 - Fa0/1
• R2 - S0/0
• R4 - Fa0/0
• R5 - Fa0/0
• R5 - S0/0

R1 Configuration:

!

ip multicast-routing

!

interface FastEthernet0/0
 ip address 10.1.14.1 255.255.255.0
 ip pim sparse-mode
 speed 100
 full-duplex

!

interface Serial0/0.125 multipoint
 ip address 10.1.125.1 255.255.255.0
 ip pim sparse-mode
 ip ospf network point-to-multipoint
 snmp trap link-status
 frame-relay map ip 10.1.125.2 102 broadcast
 frame-relay map ip 10.1.125.5 105 broadcast
 frame-relay map ip 10.1.125.1 102
!

R2 Configuration:

!

ip multicast-routing

!

interface FastEthernet0/0
 ip address 10.1.25.2 255.255.255.0
 ip pim sparse-mode
 speed 100
 full-duplex
!

interface FastEthernet0/1
 ip address 10.1.26.2 255.255.255.0
 ip pim sparse-mode
 speed 100
 full-duplex
!

interface Serial0/0
 ip address 10.1.125.2 255.255.255.0
 ip pim sparse-mode
 encapsulation frame-relay
 ip ospf network point-to-multipoint
 clock rate 2000000
 frame-relay map ip 10.1.125.2 201
 frame-relay map ip 10.1.125.1 201 broadcast
 frame-relay map ip 10.1.125.5 201
 no frame-relay inverse-arp
!

R4 Configuration:

!

ip multicast-routing

!

interface FastEthernet0/0
 ip address 10.1.14.4 255.255.255.0
 ip pim sparse-mode
 speed 100
 full-duplex
!

R5 Configuration:

!

ip multicast-routing

!

interface FastEthernet0/0
 ip address 10.1.25.5 255.255.255.0
 ip pim sparse-mode
 speed 100
 full-duplex

!

interface Serial0/0
 ip address 10.1.125.5 255.255.255.0
 ip pim sparse-mode
 encapsulation frame-relay
 ip ospf network point-to-multipoint
 clock rate 2000000
 frame-relay map ip 10.1.125.1 501 broadcast
 frame-relay map ip 10.1.125.2 501
 frame-relay map ip 10.1.125.5 501
!

Verification:

Pic.2 - PIM Neighbors of R1.

Pic. 3 - PIM Neighbors of R2.

Task 2

Configure R2 to be BSR and R5 to be RP. Use the most stable interface on R2 and R5 to accomplish the task.

R2 Configuration:

!

interface Loopback102
 ip address 172.16.102.1 255.255.255.255
 ip pim sparse-mode
!

ip pim bsr-candidate Loopback102 0

!

R5 Configuration:

!

interface Loopback105
 ip address 172.16.105.1 255.255.255.128
 ip pim sparse-mode
!

ip pim rp-candidate Loopback105

!

Verification:

Pic. 4 - RP Information on R4.

Pic. 5 - RP Information on R5.

Note!

The RP candidate uses default priority 0 (Cisco implementation, whereas the standard uses 192, max. 255). RP with the LOWEST priority (0) is preferred.
http://www.cisco.com/en/US/docs/ios/ipmulti/command/reference/imc_04.html#wp1055223

In PIMv2, a BSR is the equivalent of Mapping Agent used in Auto-RP. BSR default priority is 0 (0-255). Candidate with the HIGHEST priority is preferred if multiple BSR candidates exist.

http://www.cisco.com/en/US/docs/ios/ipmulti/command/reference/imc_04.html#wp1053348

BSR does NOT elect the best RP. The group range to RP mapping is only distributed distributed to routers and they choose the best one for a group.

This information is disseminated on a hop-by-hop basis.

Task 3

Use R4 to simulate multicast server sending packets to 224.46.46.46. Users on VLAN 26 should receive this multicast feed. Verify your solution.

R6 Configuration:

!

interface FastEthernet0/0
 ip address 10.1.26.6 255.255.255.0
 ip igmp join-group 224.46.46.46
 speed 100
 full-duplex

!

Verification:

Pic. 6 - Mroute Table on R2.

Pic. 7 - Mroute Table on R5.

Note!
R5 is the RP for all multicast groups. In the output the RPF nbr 0.0.0.0 implies this fact. The (*,G) entries show up in the client-to-RP path as expected).

Pic. 8 - Ping (server feed) from R4 results.