HP A5500 EI Switch Series, Руководство по настройке

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the largest value will take effect. If you want to enable neighbor tracking, be sure to enable the
neighbor tracking feature on all PIM routers on a multi-access subnet.
The LAN-delay setting will cause the upstream routers to delay processing received prune messages. The
override-interval sets the length of time that a downstream router can wait before sending a prune
override message. When a router receives a prune message from a downstream router, it does not
perform the prune action immediately. Instead, it maintains the current forwarding state for a period of
LAN-delay plus override-interval. If the downstream router needs to continue receiving multicast data, it
must send a join message within the prune override interval. Otherwise, the upstream router will perform
the prune action when the period of LAN-delay plus override-interval times out.
A hello message sent from a PIM router contains a generation ID option. The generation ID is a random
value for the interface on which the hello message is sent. Normally, the generation ID of a PIM router
does not change unless the status of the router changes (for example, when PIM is just enabled on the
interface or the device is restarted). When the router starts or restarts sending hello messages, it
generates a new generation ID. If a PIM router finds that the generation ID in a hello message from the
upstream router has changed, it assumes that the status of the upstream neighbor is lost or that the
upstream neighbor has changed. In this case, it triggers a join message for state update.
If you disable join suppression (namely, enable neighbor tracking), be sure to disable the join
suppression feature on all PIM routers on a multi-access subnet. Otherwise, the upstream router will fail
to explicitly track which downstream routers have joined to it.
Configuring hello options globally
Follow these steps to configure hello options globally:
To do... Use the command... Remarks
Enter system view system-view —
Enter public network PIM view or
VPN instance PIM view pim [ vpn-instance vpn-instance-
name ]
—
Configure the priority for DR
election
hello-option dr-priority priority
Optional
1 by default.
Configure PIM neighbor timeout
time
hello-option holdtime interval
Optional
105 seconds by default.
Configure the prune message
delay time (LAN-delay)
hello-option lan-delay interval
Optional
500 milliseconds by default.
Configure the prune override
interval hello-option override-interval
interval
Optional
2,500 milliseconds by default.
Disable join suppression hello-option neighbor-tracking
Required
Enabled by default.
Configuring hello options on an interface
Follow these steps to configure hello options on an interface:
To do... Use the command... Remarks
Enter system view system-view —
Enter interface view
interface interface-type interface-
number
—