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h1. Setup chronyd

h2. Requirements

To install chronyd you will need the following:

* a installed and supported operating system (e.g. CentOS 8.x)

* root-access

* a fast internet connection

h2. Preliminary Note

This procedure is based on a documentation taken from:

* https://www.redhat.com/sysadmin/chrony-time-services-linux

* https://www.ibm.com/docs/en/ess/6.1.0_ent?topic=guide-how-set-up-chronyd-time-server

h2. Install 

<pre><code class="bash">

yum install chronyd

</code></pre>

h2. Start/Enable Service

<pre><code class="bash">

systemctl enable chronyd

systemctl start chronyd

</code></pre>

When you are not running the CentOS Firewall yet, then start it:

<pre><code class="shell">

systemctl enable firewalld

systemctl start firewalld

</code></pre>

add chronyd to the firewall if you are going to serve ntp

<pre><code class="shell">

firewall-cmd --add-service=ntp --permanent

firewall-cmd --reload

</code></pre>

h2. config

Edit the @/etc/chrony.conf@ file.

<pre>

# add offset to source ... this shouldn't be necessary at all!

pool 2.fedora.pool.ntp.org iburst offset 7200

# add one specific ntp-server

server 10.11.12.14 iburst prefer

#allow clients to connect from

allow 10.12.100.0/24

#set local stratum in case no external source is available

#set it as low as possible to give clients a choice on better sources

local stratum 4

</pre>

h2. Status

<pre><code class="shell">

chronyc sources

chronyc burst 4/4

</code></pre>