HP 6125XLG - Configuring Multicast Source Registration

103
Ste
p
Command Remarks
1. Enter system view.
system-view
N/A
2. Enter interface view.
interface interface-type
interface-number
N/A
3. Configure a PIM domain
border.
pim bsr-boundary
By default, no PIM domain border
is configured.
Disabling the BSM semantic fragmentation function
Generally, a BSR periodically advertises the RP-set information in BSMs within the PIM-SM domain. It
encapsulates a BSM in an IP datagram. When a BSM exceeds the MTU, it is split into multiple BSM
fragments (BSMFs). The loss of a single IP fragment leads to unavailability of the entire message.
Semantic fragmentation of BSMs can solve this issue. When a non-BSR receives a BSMF, it examines the
RP-set information for a multicast group range:
• If the RP-set information is carried in one BSMF, the router directly updates the RP-set information for
the group range.
• If the RP-set information is carried in multiple BSMFs, the router updates the RP-set information for the
group range after receiving all these BSMFs. The 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. Therefore, the device learns only part of the RP-set
information. If such devices exist in the PIM-SM domain, you must disable the BSM 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 PIM view.
pim [ vpn-instance
vpn-instance-name ]
N/A
3. Disable the BSM semantic
fragmentation function.
undo bsm-fragment enable
By default, BSM semantic
fragmentation is enabled.
NOTE:
Generally, a BSR performs BSM semantic fragmentation according to the MTU of its BSR interface. For
BSMs originated due to learning of a new PIM neighbor, semantic fra
g
mentation is performed accordin
g
to the MTU of the interface that sends the BSMs.
Configuring multicast source registration
In a PIM-SM domain, the source-side DR sends register messages to the RP, and these register messages
have different multicast source or group addresses. To limit the multicast groups to which a RP is
designated, you can configure an ACL to filter register messages. Under the following conditions, the RP
sends a register-stop message to the DR to stop the registration process.
• The register message of a (S, G) entry is denied by the ACL.
• The ACL does not define a deny or permit action for a matching register message.