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Configuring C-BSR timers
The BSR election winner multicasts its own IP address and RP-Set information through bootstrap messages
within the entire zone it serves. The BSR floods bootstrap messages throughout the network at the interval
of BS (BSR state) period. Any C-BSR that receives a bootstrap message retains the RP-set for the length of
BS timeout, during which no BSR election takes place. If no bootstrap message is received from the BSR
before the BS timeout timer expires, a new BSR election process is triggered among the C-BSRs.
Perform the following configuration on C-BSR routers.
Follow these steps to configure C-BSR timers:
To do…
Use the command…
Remarks
Enter system view
system-view
—
Enter public network PIM view or
VPN instance PIM view
pim
[
vpn-instance
vpn-instance-name
]
—
Configure the BS period
c-bsr interval
interval
Optional
For the default value, see the
note under this table.
Configure the BS timeout timer
c-bsr holdtime
interval
Optional
For the default value, see the
note under this table.
NOTE:
About the BS period:
•
By default, the BS period is determined by the formula “BS period = (BS timeout – 10) / 2”. The
default BS timeout is 130 seconds, so the default BS period = (130 – 10) / 2 = 60 (seconds).
•
If this parameter is manually configured, the system will use the configured value.
About the BS timeout timer:
•
By default, the BS timeout value is determined by the formula “BS timeout timer = BS period × 2 +
10”. The default BS period is 60 seconds, so the default BS timeout timer = 60 × 2 + 10 = 130
(seconds).
•
If this parameter is manually configured, the system will use the configured value.
CAUTION:
In configuration, make sure that the BS period value is smaller than the BS timeout value.
Disabling BSM semantic fragmentation
Generally, a BSR periodically distributes the RP-set information in bootstrap messages within the BIDIR-
PIM domain. It encapsulates a BSM in an IP datagram and might split the datagram into fragments if the
message exceeds the maximum transmission unit (MTU). In respect of such IP fragmentation, loss of a
single IP fragment leads to unavailability of the entire message.
Semantic fragmentation of BSMs can solve this issue. When a BSM exceeds the MTU, it is split to
multiple bootstrap message fragments (BSMFs).
•
Upon receiving a BSMF that contains the RP-set information of one group range, a non-BSR router
updates corresponding RP-set information directly.
Содержание A5500 EI Switch Series
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