Edge-Core ECS4660-28F, Руководство по управлению, Страница: 853 / 2020

C
HAPTER
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| Multicast Routing
Configuring PIMv6 for IPv6
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want to continue receiving the flow referenced in a LAN prune delay
message, then the propagation delay represents the time required for
the LAN prune delay message to be propagated down from the
upstream router to all downstream routers attached to the same VLAN
interface.
◆
Trigger Hello Delay – The maximum time before transmitting a
triggered PIM Hello message after the router is rebooted or PIM is
enabled on an interface. (Range: 0-5 seconds; Default: 5 seconds)
When a router first starts or PIM is enabled on an interface, the hello
delay is set to random value between 0 and the trigger hello delay. This
prevents synchronization of Hello messages on multi-access links if
multiple routers are powered on simultaneously.
Also, if a Hello message is received from a new neighbor, the receiving
router will send its own Hello message after a random delay between 0
and the trigger hello delay.
Dense-Mode Attributes
◆ Graft Retry Interval – The time to wait for a Graft acknowledgement
before resending a Graft message. (Range: 1-10 seconds; Default: 3
seconds)
A graft message is sent by a router to cancel a prune state. When a
router receives a graft message, it must respond with an graft
acknowledgement message. If this acknowledgement message is lost,
the router that sent the graft message will resend it a number of times
(as defined by Max. Graft Retries).
◆ Max. Graft Retries – The maximum number of times to resend a Graft
message if it has not been acknowledged. (Range: 1-10; Default: 3)
◆ State Refresh Origination Interval – The interval between sending
PIM-DM state refresh control messages. (Range: 1-100 seconds;
Default: 60 seconds)
The pruned state times out approximately every three minutes and the
entire PIM-DM network is reflooded with multicast packets and prune
messages. The state refresh feature keeps the pruned state from
timing out by periodically forwarding a control message down the
distribution tree, refreshing the prune state on the outgoing interfaces
of each router in the tree. This also enables PIM routers to recognize
topology changes (sources joining or leaving a multicast group) before
the default three-minute state timeout expires.
This command is only effectively for interfaces of first hop, PIM-DM
routers that are directly connected to the sources of multicast groups.
Sparse-Mode Attributes
◆ DR Priority – Sets the priority advertised by a router when bidding to
become the Designated Router (DR). (Range: 0-4294967294;
Default: 1)
More than one PIM-SM router may be connected to an Ethernet or
other shared-media LAN. If multicast hosts are directly connected to