HP 6125G HP 6125G & 6125G/XG Blade Switches IP Multicast Configuration - Page 170

Intra-domain Anycast RP through MSDP, Usually an Anycast RP address is con d on a logic interface

Page 170 highlights

Because the SA message is from an MSDP peer (RP 3) in the same mesh group, RP 4 and RP 5 both accept the SA message, but they do not forward the message to other members in the mesh group. Instead, they forward it to other MSDP peers (RP 6 in this example) out of the mesh group. 4. When RP 6 receives the SA messages from RP 4 and RP 5 (supposing RP 5 has a higher IP address): Although RP 4 and RP 5 are in the same AS (AS 3) and both are MSDP peers of RP 6, because RP 5 has a higher IP address, RP 6 accepts only the SA message from RP 5. 5. When RP 7 receives the SA message from RP 6: Because the SA message is from a static RPF peer (RP 6), RP 7 accepts the SA message and forwards it to other peer (RP 8). 6. When RP 8 receives the SA message from RP 7: A BGP or MBGP route exists between two MSDP peers in different ASs. Because the SA message is from an MSDP peer (RP 7) in a different AS, and the MSDP peer is the next hop on the BGP or MBGP route to the source-side RP, RP 8 accepts the message and forwards it to its other peer (RP 9). 7. When RP 9 receives the SA message from RP 8: Because RP 9 has only one MSDP peer, RP 9 accepts the SA message. SA messages from paths other than those described previously are not accepted or forwarded by MSDP peers. Intra-domain Anycast RP through MSDP Anycast RP refers to an application that enables load balancing and redundancy backup between two or more RPs within a PIM-SM domain by configuring the same IP address for, and establishing MSDP peering relationship between, these RPs. Usually an Anycast RP address is configured on a logic interface, like a loopback interface. An MSDP peer address must be different from the Anycast RP address. Be sure to configure a 32-bit subnet mask (255.255.255.255) for the Anycast RP address sure, which means configure the Anycast RP address into a host address. As shown in Figure 53, within a PIM-SM domain, a multicast source sends multicast data to multicast group G, and Receiver is a member of the multicast group. To implement Anycast RP, configure the same IP address (known as Anycast RP address, typically a private address) on Router A and Router B, configure these interfaces as C-RPs, and establish an MSDP peering relationship between Router A and Router B. 159

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159
Because the SA message is from an MSDP peer (RP 3) in the same mesh group, RP 4 and RP 5 both
accept the SA message, but they do not forward the message to other members in the mesh group.
Instead, they forward it to other MSDP peers (RP 6 in this example) out of the mesh group.
4.
When RP 6 receives the SA messages from RP 4 and RP 5 (supposing RP 5 has a higher IP
address):
Although RP 4 and RP 5 are in the same AS (AS 3) and both are MSDP peers of RP 6, because RP
5 has a higher IP address, RP 6 accepts only the SA message from RP 5.
5.
When RP 7 receives the SA message from RP 6:
Because the SA message is from a static RPF peer (RP 6), RP 7 accepts the SA message and
forwards it to other peer (RP 8).
6.
When RP 8 receives the SA message from RP 7:
A BGP or MBGP route exists between two MSDP peers in different ASs. Because the SA message
is from an MSDP peer (RP 7) in a different AS, and the MSDP peer is the next hop on the BGP or
MBGP route to the source-side RP, RP 8 accepts the message and forwards it to its other peer (RP
9).
7.
When RP 9 receives the SA message from RP 8:
Because RP 9 has only one MSDP peer, RP 9 accepts the SA message.
SA messages from paths other than those described previously are not accepted or forwarded by MSDP
peers.
Intra-domain Anycast RP through MSDP
Anycast RP refers to an application that enables load balancing and redundancy backup between two
or more RPs within a PIM-SM domain by configuring the same IP address for, and establishing MSDP
peering relationship between, these RPs.
Usually an Anycast RP address is configured on a logic interface, like a loopback interface. An MSDP
peer address must be different from the Anycast RP address.
Be sure to configure a 32-bit subnet mask (255.255.255.255) for the Anycast RP address sure, which
means configure the Anycast RP address into a host address.
As shown in
Figure 53
, within a PIM-SM domain, a multicast source sends multicast data to multicast
group G, and Receiver is a member of the multicast group. To implement Anycast RP, configure the same
IP address (known as Anycast RP address, typically a private address) on Router A and Router B,
configure these interfaces as C-RPs, and establish an MSDP peering relationship between Router A and
Router B.