H3C S3610-28P Operation Manual page 800

Operation Manual – Multicast Protocol
H3C S3610&S5510 Series Ethernet Switches
maintains the current forwarding state for a period of time defined by LAN-delay. If the
downstream router needs to continue receiving multicast data, it must send a prune
override message within the prune override interval; otherwise, the upstream route will
perform the prune action when the LAN-delay timer 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 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), the upstream router
will explicitly track which downstream routers are joined to it. The join suppression
feature should be enabled or disabled on all PIM routers on the same subnet.
I. Configuring hello options globally
Follow these steps to configure hello options globally:
Enter system view
Enter PIM view
Configure the priority for
DR election
Configure PIM neighbor
timeout time
Configure the prune delay
time (LAN-delay)
Configure the prune
override interval
Disable join suppression
II. Configuring hello options on an interface
Follow these steps to configure hello options on an interface:
To do...
system-view
pim
hello-option dr-priority
priority
hello-option holdtime
interval
hello-option lan-delay
interval
hello-option
override-interval interval
hello-option
neighbor-tracking
Use the command...
6-35
Chapter 6 PIM Configuration
Remarks
—
—
Optional
1 by default
Optional
105 seconds by default
Optional
500 milliseconds by
default
Optional
2,500 milliseconds by
default
Optional
Enabled by default