HP VPN Firewall Appliances Network Management Configuration Guide

615
Ste
p
Command Remarks
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 = 60 × 2 + 10
= 130 (seconds).
NOTE:
If you confi
g
ure the BS period or the BS timeout timer, the system uses the confi
g
ured one instead of the
default one.
Disabling BSM semantic fragmentation
Generally, a BSR periodically distributes the RP-set information in bootstrap messages within the PIM-SM
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.
Because the RP-set information contained in each segment is different, loss of some IP fragments will not
result in dropping of the entire message.
Generally, a BSR performs BSM semantic fragmentation according to the MTU of its BSR interface.
However, the semantic fragmentation of BSMs originated due to learning of a new PIM neighbor is
performed according to the MTU of the outgoing interface.
The function of BSM semantic fragmentation is enabled by default. A device that does not support this
function might regard a fragment as an entire message and learns only part of the RP-set information.
Therefore, if such devices exist in the PIM-SM domain, you need to disable the semantic fragmentation
function on the C-BSRs.
To disable the BSM semantic fragmentation function:
Ste
p
Command Remarks
1. Enter system view.
system-view N/A
2. Enter public network PIM view.
pim N/A
3. Disable the BSM semantic
fragmentation function.
undo bsm-fragment enable
By default, the BSM semantic
fragmentation function is enabled.
Configuring administrative scoping
When administrative scoping is disabled, a PIM-SM domain has only one BSR. The BSR manages the
whole network. To manage your network more effectively and specifically, partition the PIM-SM domain