This document explains how to configure ospf hello-interval.

What is hello-interval?

Hello interval—Routing devices send hello packets at a fixed interval on all interfaces, including virtual links, to establish and maintain neighbor relationships. The hello interval specifies the length of time, in seconds, before the routing device sends a hello packet out of an interface. This interval must be the same on all routing devices on a shared network. By default, the routing device sends hello packets every 10 seconds (broadcast and point-to-point networks) and 30 seconds (nonbroadcast multiple access (NBMA) networks).

OSPF routing devices constantly track the status of their neighbors, sending and receiving hello packets that indicate whether each neighbor still is functioning, and sending and receiving link-state advertisement (LSA) and acknowledgment packets. OSPF sends packets and expects to receive packets at specified intervals.

Below are the commands to configure ospf hello-interval on interface:

set protocols ospf area <area_id> interface <interface_name> hello-interval <hello-interval> 

set protocols ospf area <area_id> peer-interface <peer_interface_name> hello-interval <hello-interval> 

For more information on ospf hello timers, please refer: https://www.juniper.net/documentation/us/en/software/junos/ospf/topics/topic-map/configuring-ospf-timers.html#:~:text=By%20default%2C%20the%20routing%20device%20sends%20hello%20packets%20every%2010%20seconds.