R3721-F3210-F3171-HP High-End Firewalls Network Management Configuration Guide-6PW101

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Configuring SA messages related parameters
Configuration prerequisites
Before you configure SA message delivery, complete the following tasks:
• Configure any unicast routing protocol so that all devices in the domain are interoperable at the
network layer
• Configuring basic functions of MSDP
• Determine the ACL rules for filtering SA request messages
• Determine the ACL rules as SA message creation rules
• Determine the ACL rules for filtering SA messages to be received and forwarded
• Determine the TTL threshold for multicast packet encapsulation in SA messages
• Determine the maximum number of (S, G) entries learned from the specified MSDP peer that the
router can cache
Configuring SA message content
Some multicast sources send multicast data at an interval longer than the aging time of (S, G) entries. In
this case, the source-side DR must encapsulate multicast data packet by packet in register messages and
send them to the source-side RP. The source-side RP transmits the (S, G) information to the remote RP
through SA messages. Then the remote RP joins the source-side DR and builds an SPT. Because the (S, G)
entries have timed out, remote receivers can never receive the multicast data from the multicast source.
After the source-side RP is enabled to encapsulate multicast data in SA messages, if the RP wants to sends
a multicast packet, it encapsulates the multicast packet in an SA message and sends it. After receiving the
SA message, the remote RP de-encapsulates the SA message and delivers the multicast packet to the
receivers in the local domain along the RPT.
The MSDP peers deliver SA messages to one another. After receiving an SA message, a router performs
RPF check on the message. If the router finds that the remote RP address is the same as the local RP
address, it discards the SA message. In the Anycast RP application, however, you must configure RPs with
the same IP address on two or more routers in the same PIM-SM domain, and configure these routers as
MSDP peers to one another. Therefore, a logic RP address (namely the RP address on the logic interface)
that is different from the actual RP address must be designated for SA messages so that the messages can
pass the RPF check.
To configure the SA message content:
Ste
p
Command Remarks
1. Enter system view.
system-view N/A
2. Enter public network MSDP view.
msdp N/A
3. Enable encapsulation of multicast
data in SA messages.
encap-data-enable
Optional.
Disabled by default.
4. Configure the interface address as
the RP address in SA messages.
originating-rp interface-type
interface-number
Optional.
PIM RP address by default.