H3C Technologies H3C SecPath F1000-E - Manual (Page 179)

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A router may receive multiple state-refresh messages within a short time, of which some may be
duplicated messages. To keep a router from receiving such duplicated messages, you can configure the
time the router must wait before receiving the next state-refresh message. If a new state-refresh message
is received within the waiting time, the router will discard it; if this timer times out, the router will accept
a new state-refresh message, refresh its own IPv6 PIM-DM state, and reset the waiting timer.
The hop limit value of a state-refresh message decrements by 1 whenever it passes a router before it is
forwarded to the downstream node until the hop limit value comes down to 0. In a small network, a
state-refresh message may cycle in the network. To effectively control the propagation scope of
state-refresh messages, you need to configure an appropriate hop limit value based on the network size.
It is recommended to perform the following configurations on all routers in the IPv6 PIM domain.
Follow these steps to configure state-refresh parameters:
To do... Use the command... Remarks
Enter system view system-view —
Enter IPv6 PIM view pim ipv6 —
Configure the interval between
state-refresh messages
state-refresh-interval interval
Optional
60 seconds by default
Configure the time to wait before
receiving a new state-refresh
message
state-refresh-rate-limit
interval Optional
30 seconds by default
Configure the hop limit value of
state-refresh messages state-refresh-hoplimit
hoplimit-value Optional
255 by default
Configuring IPv6 PIM-DM Graft Retry Period
In IPv6 PIM-DM, graft is the only type of message that uses the acknowledgment mechanism. In an IPv6
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, namely graft retry period, until it receives a graft-ack from the upstream router.
Follow these steps to configure IPv6 PIM-DM graft retry period:
To do... Use the command... Remarks
Enter system view system-view —
Enter interface view
interface interface-type
interface-number
—
Configure graft retry period
pim ipv6 timer graft-retry
interval
Optional
3 seconds by default
NOTE:
For more information about the configuration of other timers in IPv6 PIM-DM, see Configuring IPv6 PIM
Common Timers .