R3303-HP HSR6800 Routers IP Multicast Configuration Guide

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Configuring C-BSR timers
The BSR election winner multicasts its own IPv6 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 timer, during which no BSR election takes place. If no bootstrap message is
received from the BSR when the BS timeout timer expires, a new BSR election process is triggered among
the C-BSRs.
Perform the following configuration on C-BSR routers.
To configure C-BSR timers:
Ste
p
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.
By default, the BS period is
determined by the formula "BS
period = (BS timeout timer – 10) /
2". The default BS timeout timer is
130 seconds, so the default BS
period is (130 – 10) / 2 = 60
(seconds).
The BS period value must be
smaller than the BS timeout timer.
4. Configure the BS timeout
timer.
c-bsr holdtime interval
Optional.
By default, the BS timeout timer 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 is 60 × 2 + 10 = 130
(seconds).
NOTE:
If you configure the BS period or the BS timeout timer, the system uses the configured one instead of the
default one.
Disabling BSM semantic fragmentation
Generally, a BSR periodically distributes the RP-set information in bootstrap messages within the IPv6
BIDIR-PIM domain. It encapsulates a BSM in an IP datagram and might split the datagram into fragments
if the message exceeds the 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
BSMFs.
• After receiving a BSMF that contains the RP-set information of one group range, a non-BSR router
updates corresponding RP-set information directly.
• If the RP-set information of one group range is carried in multiple BSMFs, a non-BSR router updates
corresponding RP-set information after receiving all these BSMFs.