Configuring PIM Anycast RP
A new PIM CLI is introduced for PIM Anycast RP under the router pim sub mode. The PIM CLI specifies mapping of the RP and the Anycast RP peers.
To configure PIM Anycast RP, enter the following command.
device(config)#router pim device(config-pim-router)#rp-address 100.1.1.1 device(config-pim-router)#anycast-rp 100.1.1.1 my-anycast-rp-set-acl
Syntax: [no] anycast-rp rp-address anycast-rp-set-acl
The rp address parameter specifies a shared RP address used among multiple PIM routers.
The anycast-rp-set-acl parameter specifies a host based simple acl used to specifies the address of the Anycast RP set, including a local address.
The following example is a configuration of PIM Anycast RP 100.1.1.1.The example avoids using loopback 1 interface when configuring PIM Anycast RP because the loopback 1 address could be used as a router-id. A PIM First Hop router will register the source with the closest RP. The first RP that receives the register will re-encapsulate the register to all other Anycast RP peers. Please refer to Figure 10 as described in the configuration of PIM Anycast RP 100.1.1.1.
device(config)#interface loopback 2 device(config-lbif-2)#ip address 100.1.1.1/24 device(config-lbif-2)#ip pim-sparse device(config-lbif-2)#interface loopback 3 device(config-lbif-3)#ip address 1.1.1.1/24 device(config-lbif-3)#ip pim-sparse device(config-lbif-3)#router pim device(config-pim-router)#rp-address 100.1.1.1 device(config-pim-router)#anycast-rp 100.1.1.1 my-anycast-rp-set device(config-pim-router)#ip access-list standard my-anycast-rp-set device(config-std-nacl)#permit host 1.1.1.1 device(config-std-nacl)#permit host 2.2.2.2 device(config-std-nacl)#permit host 3.3.3.3
The RP shared address 100.1.1.1 is used in the PIM domain. IP addresses 1.1.1.1, 2.2.2.2, and 3.3.3.3 are listed in the ACL that forms the self inclusive Anycast RP set. Multiple anycast-rp instances can be configured on a system; each peer with the same or different Anycast RP set.
The example shown in the following figure is a PIM Anycast-enabled network with 3 RPs, 1 PIM-FH router connecting to its active source and local receiver. Loopback 2 in RP1, RP2, and RP3 have the same IP addresses 100.1.1.1. Loopback 3 in RP1, RP2, and RP3 each have separate IP addresses configured to communicate with their peers in the Anycast RP set.