HP MSR2000/3000/4000 Router Series IP Multicast Configuration Guide

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If the router receives a new state refresh message within the specified waiting time, it discards the
message. If this timer times out, the router accepts a new state refresh message, refreshes its own PIM-DM
state, and resets the waiting timer.
The TTL value of a state refresh message decrements by 1 whenever it passes a router before it is
forwarded to the downstream node until the TTL value comes down to 0. In a small network, a state
refresh message might cycle in the network. To effectively control the propagation scope of state refresh
messages, configure an appropriate TTL value based on the network size on the router directly connected
with the multicast source.
To configure state refresh parameters:
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. Configure the interval to send state
refresh messages.
state-refresh-interval interval
By default, the interval to send
state refresh messages is 60
seconds.
4. Configure the time to wait before
receiving a new state refresh
message.
state-refresh-rate-limit time
By default, the waiting time is
30 seconds.
5. Configure the TTL value of state
refresh messages.
state-refresh-ttl ttl-value
By default, the TTL value of
state refresh messages is 255.
Configuring PIM-DM graft retry timer
In PIM-DM, graft is the only type of message that uses the acknowledgment mechanism. In a PIM-DM
domain, if a router does not receive a graft-ack message from the upstream router within the specified
time after it sends a graft message, the router keeps sending new graft messages at a configurable
interval known as graft retry timer, until it receives a graft-ack message from the upstream router. For more
information about the configuration of other timers in PIM-DM, see "Configuring common PIM timers."
To configure the graft retry timer:
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 the graft retry timer.
pim timer graft-retry interval
By default, the graft retry timer is 3
seconds.