H3C Technologies H3C S3600 Series Switches - Manual (Page 439)

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z In the case that all the peers use the rp-policy keyword: Multiple static RPF peers function at the
same time. RPs in SA messages are filtered based on the configured prefix list, and only the SA
messages whose RP addresses pass the filtering are received. If multiple static RPF peers using
the same rp-policy keyword are configured, when any of the peers receives an SA message, it will
forward the SA message to other peers.
z None of the peers use the rp-policy keyword: Based on the configured sequence, only the first
static RPF peer whose connection state is UP is active. All the SA messages from this peer will be
received, while the SA messages from other static RPF peers will be discarded. Once the active
static RPF peer fails (because the configuration is removed or the connection is terminated), based
on the configuration sequence, the subsequent first static RPF peer whose connection is in the UP
state will be selected as the active static RPF peer.
Configuration Prerequisites
Before configuring basic MSDP functions, you need to configure:
z A unicast routing protocol
z PIM-SM basic functions
Configuring MSDP Basic Functions
Follow these steps to configure MSDP basic functions:
To do... Use the command... Remarks
Enter system view system-view —
Enable MSDP function and
enter MSDP view
msdp
Required
Disabled by default
Create an MSDP peer
connection
peer peer-address
connect-interface
interface-type interface-number Required
No MSDP peer connection is
created by default.
Configure a static RPF peer
static-rpf-peer peer-address
[ rp-policy ip-prefix-name ]
Optional
No static RFP is configured by
default.
Configuring Connection Between MSDP Peers
An AS may contain multiple MSDP peers. To avoid SA flooding between the MSDP peers, you can use
the MSDP mesh mechanism to improve traffic. When multiple MSDP peers are fully connected with one
another, these MSDP peers form a mesh group.
When an MSDP peer in the mesh group receives SA messages from outside the mesh group, it sends
them to other members of the group. On the other hand, a mesh group member does not perform RPF
check on SA messages from within the mesh group and does not forward the messages to other
members of the mesh group. This avoids SA message flooding since it is unnecessary to run BGP or
MBGP between MSDP peers, thus simplifying the RPF checking mechanism.
The sessions between MSDP peers can be terminated and reactivated sessions as required. When a
session between MSDP peers is terminated, the TCP connection is closed, and there will be no
reconnection attempts. However, the configuration information is kept.