Modifying The Pim Hello Interval - Juniper ACX1000 Configuration Manual

Release History Table

Modifying the PIM Hello Interval

Copyright © 2017, Juniper Networks, Inc.
Chapter 22: Configuring Multicast Listener Discovery and Protocol-Independent Multicast
Release Description
15.2 Starting in Junos OS Release 15.2, it is no longer necessary to configure
the PIM version.
Routing devices send hello messages at a fixed interval on all PIM-enabled interfaces.
By using hello messages, routing devices advertise their existence as PIM routing devices
on the subnet. With all PIM-enabled routing devices advertised, a single designated router
for the subnet is established.
When a routing device is configured for PIM, it sends a hello message at a 30-second
default interval. The interval range is from 0 through 255. When the interval counts down
to 0, the routing device sends another hello message, and the timer is reset. A routing
device that receives no response from a neighbor in 3.5 times the interval value drops
the neighbor. In the case of a 30-second interval, the amount of time a routing device
waits for a response is 105 seconds.
If a PIM hello message contains the hold-time option, the neighbor timeout is set to the
hold-time sent in the message. If a PIM hello message does not contain the hold-time
option, the neighbor timeout is set to the default hello hold time.
To modify how often the routing device sends hello messages out of an interface:
This example shows the configuration for the routing instance. Configure the interface
1.
globally or in the routing instance.
[edit routing-instances PIM.master protocols pim interface fe-3/0/2.0]
user@host# set hello-interval 255
Verify the configuration by checking the
2.
the
show pim neighbors detail
user@host> show pim neighbors detail
Instance: PIM.master
Interface: fe-3/0/2.0
Address: 192.168.195.37, IPv4, PIM v2, Mode: Sparse
Hello Option Holdtime: 255 seconds
Hello Option DR Priority: 1
Hello Option LAN Prune Delay: delay 500 ms override 2000 ms
Join Suppression supported
Rx Join: Group Source Timeout
225.1.1.1 192.168.195.78 0
225.1.1.1 0
Interface: lo0.0
Address: 10.255.245.91, IPv4, PIM v2, Mode: Sparse
Hello Option Holdtime: 255 seconds
Hello Option DR Priority: 1
Hello Option LAN Prune Delay: delay 500 ms override 2000 ms
Join Suppression supported
Hello Option Holdtime
command.
field in the output of
681