3Com SuperStack 4 Configuration Manual page 185

Repeat this configuration to enable PIM-SM on other interfaces. Only one
multicast routing protocol can be enabled on an interface at a time.
Once enabled PIM-SM on an interface, PIM-DM cannot be enabled on the same
interface and vice versa.
Configuring the PIM-SM Domain Border
After the PIM-SM domain border is configured, bootstrap messages cannot cross
the border in any direction. In this way, the PIM-SM domain can be split.
Perform the following configuration in Interface view.
Table 212 Configuring the PIM-SM domain border
Operation
Set the PIM-SM domain border
Remove the PIM-SM domain border
configured
By default, no domain border is set. After this configuration is performed, a
bootstrap message cannot cross the border but other PIM packets can. This
configuration can effectively divide a network into domains using different BSRs.
Entering the PIM View
Global parameters of PIM should be configured in PIM view.
Perform the following configuration in system view.
Table 213 Entering the PIM view
Operation
Enter the PIM view
Back to system view
Using command, you can clear the configuration in PIM view, and back
undo pim
to system view.
Configuring Candidate-BSRs
In a PIM domain, one or more candidate BSRs should be configured. A BSR
(Bootstrap Router) is elected among candidate BSRs. The BSR takes charge of
collecting and advertising RP information.
The automatic election among candidate BSRs operates as follows:
One interface which has started PIM-SM must be specified when configuring
■
the router as the candidate BSR.
At first, each candidate BSR considers itself as the BSR of the PIM-SM domain,
■
and sends a Bootstrap message by taking the IP address of the interface as the
BSR address.
When receiving Bootstrap messages from other routers, the candidate BSR will
■
compare the BSR address of the newly received Bootstrap message with that of
itself. Comparison standards include priority and IP address. The bigger IP
Command
pim bsr-boundary
undo pim bsr-boundary
Command
pim
undo
PIM-SM Overview 197