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- All right.

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In Linux time, time synchronization
is pretty important.

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So how does that work?

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Well, to start with
use timedatectl set-ntp

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which enables or disables
time synchronization.

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That should be on by default.

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Timedatectl timesync-status

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will show you timesync-status information.

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And if you want more detail

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on a system that is
using the chrony service

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which is the case for Red Hat,

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you can use chronyc sources
and chronyc tracking.

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For much and really, much more information

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about time synchronization
and the current status.

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Let's go check this out.

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So to start with sudo timedatectl

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timesync-status

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is showing us,

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oh the name is not activatable.

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Activatable, what does that mean?

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Well, let's further investigate.

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I am going to use timedatectl set,

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timedatectl status,

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and there we can see

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NTP service: active

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and system clock synchronized.

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So all of that is looking good.

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Now as this timedatectl

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timesync status is giving
some weird message.

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I want to further investigate.

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So sudo chrony,

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chronyc sources

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is what we are going to use.

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And this is showing

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the time sources that
are actually being used.

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And you know what's going on.

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I think I understand what's going on.

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If you use sudo systemctl

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status

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chrony, chronyd

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then we can see that
chronyd service is running.

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Now it happens to be
that nowadays in Linux,

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there are two different
services that can be used

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for time synchronization.

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It's either chrony or systemd-timesyncd

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Systemd-timesyncd is pretty simple.

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And for that reason, you
won't find it always active.

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And here on my Red Hat family system.

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I can see chronyd service.

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And that's why timedatectl timesync-status

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is giving me, a service is not activatable

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that's because it has been
blocked out by chrony.

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Chrony is doing the work
and chronyc sources,

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as we can see here,

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is showing all the time
synchronization sources,

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including the stratum.

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So that's a reliability,
as we have just seen,

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including

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the offset in milliseconds,

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that falls far within the 1000 seconds

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limit that is allowed.

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Now, if this is not enough detail

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use sudo chrony,

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sudo chronyc tracking.

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And what is chronyc tracking giving you?

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That is giving you even more detail

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about the current time sync status.

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For most people this is
too much information.

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Chronyc sources is more than enough.

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It shows you the time sync sources

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and it's giving you
the comfortable feeling

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that you are okay.

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But if you need more detail, here you go.

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More detail using chronyc tracking.