Configuring global context commands

NOTE:

PIM-SM operation requires an IP routing protocol enabled on the router. You can use RIP, OSPF, and/or static routing. The examples in this section use RIP.

Syntax:


ip routing
no ip routing

Enables IP routing on the router.

The no form of the command disables IP routing. Note that before disabling IP routing, it is necessary to disable all other IP routing protocols on the router.

(Default: Disabled)

Syntax:


ip multicast-routing
no ip multicast-routing

Enables or disables IP multicast routing on the router. IP routing must first be enabled. Note that router PIM must be disabled before disabling IP multicast routing.

(Default: Disabled)

Syntax:


router [ospf | rip]
no router [ospf | rip]

 ip route [ip-addr/mask-len] [ip-addr | vlan | reject | blackhole]
no ip route [ip-addr/mask-len] [ip-addr | vlan | reject | blackhole]

These commands are the options for the IP routing protocol required to support PIM operation.

Syntax:


no router pim [[enable] | [disable]]

Puts the CLI into the PIM context level. IP routing must be enabled before enabling PIM.

The no router pim command deletes the PIM configuration. (Default: Disabled)

[enable]

Enables PIM globally.

[disable]

Disables PIM globally. Disabling PIM does not delete the PIM configuration.

Configuring for PIM support at the global level

Using the topology shown in the following figure, router "B" is directly connected to the DR for multicast group "X." In this case, suppose that you want to globally configure router "B" for PIM operation. On the global level, you would enable the following:
  • IP routing

  • IP multicast routing

  • An IP routing protocol (RIP, OSPF, or static routing; use RIP for this example)

Figure 10: PIM-SM domain with SPT active to support a host that has joined a multicast group

Global configuration for supporting PIM-SM operation

switch(config)# ip routing
switch(config)# ip multicast-routing
switch(config)# router rip
switch(rip)# exit
switch(config)# router pim
switch(pim)# exit
switch(config)#
Figure 11: Displaying the running configuration