Juniper ACX2000 Configuration Guide

Release History Table DescriptionRelease
Starting in Junos OS Release 15.2, it is no longer necessary to configure
the PIM version.
15.2
Modifying the PIM Hello Interval
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:
1. This example shows the configuration for the routing instance. Configure the interface
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
2. Verify the configuration by checking the Hello Option Holdtime field in the output of
the show pim neighbors detail command.
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
681Copyright © 2017, Juniper Networks, Inc.
Chapter 22: Configuring Multicast Listener Discovery and Protocol-Independent Multicast

Juniper ACX2000 Specifications

General

Brand	Juniper
Model	ACX2000
Category	Network Router
Language	English