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Catalyst 3750 SwitchSoftware Configuration Guide
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Chapter47 Configuring MSDP
Configuring MSDP
Note that the ip msdp originator-id global configuration command also identifies an interface to be
used as the RP address. If both the ip msdp border sa-address and the ip msdp originator-id global
configuration commands are configured, the address derived from the ip msdp originator-id command
specifies the RP address.
To return to the default setting (active sources in the dense-mode region do not participate in MSDP),
use the no ip msdp border sa-address interface-id global configuration command.
Configuring an Originating Address other than the RP Address
You can allow an MSDP speaker that originates an SA message to use the IP address of the interface as
the RP address in the SA message by changing the Originator ID. You might change the Originator ID
in one of these cases:
If you configure a logical RP on multiple switches in an MSDP mesh group.
If you have a switch that borders a PIM sparse-mode domain and a dense-mode domain. If a switch
borders a dense-mode domain for a site, and sparse-mode is being used externally, you might want
dense-mode sources to be known to the outside world. Because this switch is not an RP, it would not
have an RP address to use in an SA message. Therefore, this command provides the RP address by
specifying the address of the interface.
Beginning in privileged EXEC mode, follow these steps to allow an MSDP speaker that originates an
SA message to use the IP address on the interface as the RP address in the SA message. This procedure
is optional.
If both the ip msdp border sa-address and the ip msdp originator-id global configuration commands
are configured, the address derived from the ip msdp originator-id command specifies the address of
the RP.
To prevent the RP address from being derived in this way, use the no ip msdp originator-id interface-id
global configuration command.
Step5 show running-config Verify your entries.
Step6 copy running-config startup-config (Optional) Save your entries in the configuration file.
Command Purpose
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 ip msdp originator-id interface-id Configures the RP address in SA messages to be the address of the
originating device interface.
For interface-id, specify the interface on the local switch.
Step3 end Return to privileged EXEC mode.
Step4 show running-config Verify your entries.
Step5 copy running-config startup-config (Optional) Save your entries in the configuration file.