Configuring Ipv6 Multicast Source Registration - HP 6125XLG Configuration Manual

Step
3. Configuring an IPv6 PIM
domain border.
Disabling the BSM semantic fragmentation function
Generally, a BSR periodically advertises the RP-set information in BSMs within the IPv6 PIM-SM domain.
It encapsulates a BSM in an IPv6 datagram and might fragment the datagram if the message exceeds the
MTU. In this case, 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
BSM fragments (BSMFs).
If the RP-set information for an IPv6 multicast group range is carried in one BSMF, a non-BSR router
•
directly updates the RP-set information for the group range after receiving the BSMF.
• If the RP-set information for an IPv6 multicast group range is carried in multiple BSMFs, a non-BSR
router updates the RP-set information for the group range after receiving all these BSMFs. Because
the RP-set information contained in each segment is different, loss of some IP fragments does not
result in dropping of the entire BSM.
The BSM semantic fragmentation function is enabled by default. A device that does not support this
function might regard a fragment as a BSM and thus learns only part of the RP-set information. Therefore,
if such devices exist in the IPv6 PIM-SM domain, you must disable the BSM semantic fragmentation
function on the C-BSRs.
To disable the BSM semantic fragmentation function:
Step
1. Enter system view.
2. Enter IPv6 PIM view.
3. Disable the BSM semantic
fragmentation function.
NOTE:
Generally, a BSR performs BSM semantic fragmentation according to the MTU of its BSR interface.
However, for BSMs originated due to learning of a new IPv6 PIM neighbor, semantic fragmentation is
performed according to the MTU of the interface that sends the BSMs.

Configuring IPv6 multicast source registration

In an IPv6 PIM-SM domain, the source-side DR sends register messages to the RP, and these register
messages have different IPv6 multicast source or IPv6 multicast group addresses. You can configure a
filtering rule to filter register messages so that the RP can provide services for specific IPv6 multicast
groups. If the filtering rule denies an (S, G) entry, or if the filtering rule does not define an action for this
entry, the RP sends a register-stop message to the DR to stop the registration process for the IPv6 multicast
data.
In view of information integrity of a register message in the transmission process, you can configure the
device to calculate the checksum based on the entire register message. However, to reduce the workload
of encapsulating data in register messages and for the sake of interoperability, do not use this checksum
calculation method.
Command
ipv6 pim bsr-boundary
Command
system-view
ipv6 pim
undo bsm-fragment enable
155
Remarks
By default, no IPv6 PIM domain
border is configured.
Remarks
N/A
N/A
By default, BSM semantic
fragmentation is enabled.