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PIM-DM Configuration
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Configuring the maximum number of PIM neighbor on an interface
Clearing PIM neighbors
Enabling Multicast
Enabling PIM-DM
PIM-DM needs to be enabled in configuration of all interfaces.
After PIM-DM is enabled on an interface, it will send PIM Hello messages 
periodically and process protocol packets sent by PIM neighbors.
Perform the following configuration in VLAN interface view.
It’s recommended to configure PIM-DM on all interfaces in non-special cases. This 
configuration is effective only after the multicast routing is enabled in system view.
Once enabled PIM-DM on an interface, PIM-SM cannot be enabled on the same 
interface and vice versa.
Configuring the Time 
Intervals for Ports to 
Send Hello Packets
When protocol independent multicast (PIM) protocol is enabled for a port, the 
port sends Hello packets periodically. The time intervals to send Hello packets vary 
with the bandwidth and type of the connected networks.
Perform the following configuration in interface view.
You can configure different time intervals according to the actual networks. By 
default, the time interval for sending Hello packets is 30 seconds. In general, you 
need not modify the parameter seconds.
The time interval can be configured only after the PIM protocol such as 
protocol independent multicast-dense mode (PIM-DM) protocol or protocol 
independent multicast-sparse mode (PIM-SM) protocol is enabled in interface 
view.
When you configure the time interval for a port to send Hello packets, the pim 
neighbor hold-time value automatically turns into 3.5 times the time interval 
value. Therefore you need not configure a value for pim neighbor hold-time.
Entering the PIM View
Global parameters of PIM should be configured in PIM view.
Table 447   Enable PIM-DM
Operation 
Command 
Enable PIM-DM on an interface 
pim dm 
Disable PIM-DM on an interface 
undo pim dm
Table 448   Configure the time intervals for ports to send Hello packets
Operation 
Command 
Configure the time intervals for ports to send Hello packets 
pim timer hello seconds 
Restore the default values of the time intervals 
undo pim timer hello