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BigIron RX Series Configuration Guide
53-1001810-01
PIM Sparse
23
Rendezvous Point (RP).
To enhance overall network performance, device use the RP to forward only the first packet
from a group source to the group’s receivers. After the first packet, the device calculates the
shortest path between the receiver and source (the Shortest Path Tree, or SPT) and uses the
SPT for subsequent packets from the source to the receiver. The device calculates a separate
SPT for each source-receiver pair.
NOTE
Brocade recommends that you configure the same ports as candidate BSRs and RPs.
RP paths and SPT paths
Figure 91
shows two paths for packets from the source for group 239.255.162.1 and a receiver for
the group. The source is attached to PIM Sparse router A and the recipient is attached to PIM
Sparse router C. PIM Sparse router B in is the RP for this multicast group. As a result, the default
path for packets from the source to the receiver is through the RP. However, the path through the
RP sometimes is not the shortest path. In this case, the shortest path between the source and the
receiver is over the direct link between router A and router C, which bypasses the RP (router B).
To optimize PIM traffic, the protocol contains a mechanism for calculating the Shortest Path Tree
(SPT) between a given source and receiver. PIM Sparse routers can use the SPT as an alternative to
using the RP for forwarding traffic from a source to a receiver. By default, the device forward the
first packet they receive from a given source to a given receiver using the RP path, but forward
subsequent packets from that source to that receiver through the SPT. In
Figure 91
, the device A
forwards the first packet from group 239.255.162.1’s source to the destination by sending the
packet to router B, which is the RP. Router B then sends the packet to router C. For the second and
all future packets that router A receives from the source for the receiver, router A forwards them
directly to router C using the SPT path.
NOTE
Brocade recommends that you configure the same ports as candidate BSRs and RPs
Configuring PIM Sparse
To configure a device for PIM Sparse, perform the following tasks:
•
Configure the following global parameter:
•
Enable the PIM Sparse mode of multicast routing.
•
Configure the following interface parameters:
•
Configure an IP address on the interface
•
Enable PIM Sparse.
•
Identify the interface as a PIM Sparse border, if applicable.
NOTE
You cannot configure a Brocade routing interface as a PMBR interface for PIM Sparse in the
current software release.
•
Configure the following PIM Sparse global parameters:
•
Identify the device as a candidate PIM Sparse Bootstrap Router (BSR), if applicable.
Summary of Contents for Brocade DCX
Page 40: ...xl BigIron RX Series Configuration Guide 53 1001810 01 ...
Page 72: ...lxxii BigIron RX Series Configuration Guide 53 1001810 01 ...
Page 88: ...16 BigIron RX Series Configuration Guide 53 1001810 01 Searching and filtering output 1 ...
Page 300: ...228 BigIron RX Series Configuration Guide 53 1001810 01 Displaying IP information 7 ...
Page 318: ...246 BigIron RX Series Configuration Guide 53 1001810 01 Deploying a LAG 8 ...
Page 418: ...346 BigIron RX Series Configuration Guide 53 1001810 01 SuperSpan 12 ...
Page 482: ...410 BigIron RX Series Configuration Guide 53 1001810 01 MRP CLI example 14 ...
Page 506: ...434 BigIron RX Series Configuration Guide 53 1001810 01 Displaying VSRP information 15 ...
Page 582: ...510 BigIron RX Series Configuration Guide 53 1001810 01 Viewing Layer 2 ACLs 20 ...
Page 634: ...562 BigIron RX Series Configuration Guide 53 1001810 01 Troubleshooting ACLs 21 ...
Page 642: ...570 BigIron RX Series Configuration Guide 53 1001810 01 Trunk formation 22 ...
Page 746: ...674 BigIron RX Series Configuration Guide 53 1001810 01 Displaying RIP filters 24 ...
Page 808: ...736 BigIron RX Series Configuration Guide 53 1001810 01 Displaying OSPF information 25 ...
Page 938: ...866 BigIron RX Series Configuration Guide 53 1001810 01 Displaying MBGP information 27 ...
Page 950: ...878 BigIron RX Series Configuration Guide 53 1001810 01 Using secure copy 28 ...
Page 988: ...916 BigIron RX Series Configuration Guide 53 1001810 01 Clearing IS IS information 29 ...
Page 1054: ...982 BigIron RX Series Configuration Guide 53 1001810 01 Sample 802 1x configurations 33 ...
Page 1108: ...1036 BigIron RX Series Configuration Guide 53 1001810 01 sFlow 39 ...
Page 1190: ...1118 BigIron RX Series Configuration Guide 53 1001810 01 Displaying RIPng information 44 ...
Page 1270: ...1198 BigIron RX Series Configuration Guide 53 1001810 01 Displaying ACLs 47 ...
Page 1310: ...1238 BigIron RX Series Configuration Guide 53 1001810 01 Displaying OSPFv3 information 48 ...
Page 1382: ...1310 BigIron RX Series Configuration Guide 53 1001810 01 Commands That Require a Reload D ...
Page 1435: ...BigIron RX Series Configuration Guide 1363 53 1001810 01 VSRP E ...
Page 1436: ...1364 BigIron RX Series Configuration Guide 53 1001810 01 VSRP E ...