3Com Switch 7700 Configuration Manual page 228

220 C 6: M
HAPTER ULTICAST
P
ROTOCOL
Perform the following configuration in VLAN interface view.
Table 33 Setting 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.
This command cannot create a multicast packet forwarding border but only a PIM
bootstrap message border.
Entering PIM View
Global parameters of PIM should be configured in PIM view.
Perform the following configuration in system view.
Table 34 Entering PIM View
Operation
Enter PIM view
Back to system view
Using undo pim command, you can clear the configuration in PIM view and back
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 is described 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 address is considered better when the priority is the same.
If the new BSR address is better, the candidate BSR will replace its BSR address.
Otherwise, the candidate BSR will keep its BSR address and continue to regard
itself as the BSR.
Perform the following configuration in PIM view.
Table 35 Configuring Candidate-BSRs
Operation
Configure a candidate-BSR
Command
pim bsr-boundary
undo pim bsr-boundary
Command
pim
undo pim
Command
c-bsr interface-type interface-number
hash-mask-len [ priority ]