Operation Manual – Multicast
H3C S5600 Series Ethernet Switches
Chapter 5 MSDP Configuration
5-12
SA messages cannot be transmitted between these two peers. On the other hand,
when resetting an MSDP peering relationship between faulty MSDP peers or bringing
faulty MSDP peers back to work, you can adjust the retry interval of establishing a
peering relationship through the following configuration.
Follow these steps to configure MSDP peer connection control:
To do...
Use the command...
Remarks
Enter system view
system-view
—
Enter MSDP view
msdp
—
Shut down the connection
with the specified MSDP
peer
shutdown
peer-address
Optional
By default, all MSDP
peering connections are up.
Configure the retry interval
of MSDP peer connection
establishment
timer retry seconds
Optional
30 seconds by default
5.4 Configuring SA Message Transmission
An SA message contains the IP address of the multicast source S, multicast group
address G, and RP address. In addition, it contains the first multicast data received by
the RP in the domain where the multicast source resides. For some burst multicast data,
if the multicast data interval exceeds the SA message hold time, the multicast data
must be encapsulated in the SA message; otherwise, the receiver will never receive the
multicast source information.
By default, when a new receiver joins, a router does not send any SA request message
to its MSDP peer but has to wait for the next SA message. This defers the reception of
the multicast information by the receiver. In order for the new receiver to know about
the currently active multicast source as quickly as possible, the router needs to send
SA request messages to the MSDP peer.
Generally, a router accepts all SA messages sent by all MSDP peers and sends all SA
messages to all MSDP peers. By configuring the rules for filtering SA messages to
receive/send, you can effectively control the transmission of SA messages among
MSDP peers. For forwarded SA messages, you can also configure a Time-to-Live (TTL)
threshold to control the range where SA messages carrying encapsulated data are
transmitted.
To reduce the delay in obtaining the multicast source information, you can cache SA
messages on the router. The number of SA messages cached must not exceed the
system limit. The more messages are cached, the more router memory is occupied.
