H3C Technologies H3C SecPath F1000-E - Manual (Page 883)

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Step Command Remarks
4. Configure the C-BSR priority. c-bsr priority priority
Optional.
64 by default.
Configuring C-BSR timers
The BSR election winner multicasts its own IPv6 address and RP-Set information throughout the region that
it serves through bootstrap messages. The BSR floods bootstrap messages throughout the network at the
interval of the 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 occurs. If the BSR state times out and no bootstrap
message is received from the BSR, a new BSR election process begins among the C-BSRs.
Perform the following configuration on C-BSR routers.
To configure C-BSR timers:
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter IPv6 PIM view. pim ipv6 N/A
3. Configure the BS period. c-bsr interval interval
Optional.
For the default value, see the note
after this table.
4. Configure the BS timeout. c-bsr holdtime interval
Optional.
For the default value, see the note
after 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:
• By default, the BS timeout value is determined by the formula "BS timeout = BS period × 2 + 10". The
default BS period is 60 seconds, so the default BS timeout = 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 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 IPv6
PIM-SM domain. It encapsulates a BSM in an IPv6 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).