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In this video you'll learn how
to configure time synchronization on Red Hat.

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So Red Hat uses a
crony service to manage time

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synchronization and this service is
managed by the timedatectl utility.

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Configuration of Chrony itself is
in the etccronie configuration file. That's

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where you set your time
sources to synchronize with. And next

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you use chrony C sources
to check current synchronization status.

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Let's
check.

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So I'm starting by using
sudo systemctl status of chronyd

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and there we can see
that chronyd is currently loaded.

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You can also see in the logs to the end that it's currently
synchronizing. It's having a good time and seems to be doing all right.

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Now I would like to edit
this configuration file. So sudo vim

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on etc chrony conf that's the
main configuration file. And as you

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can see, it has a pool.
And this pool is pretty reliable.

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It's a pool
of Internet time servers.

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Now if you want, you can add your
own server and I'm going to add a server

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dummy example and that should make a point.
This is a server that doesn't exist, but I

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want to show you what is happening in
case you have a server that doesn't exist.

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Now, I did just change the configuration
for Chrony, so I need to restart it.

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Let's do
that right now.

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And then I can check what is
going on first by checking on the status.

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And on the status we see what? Well, we don't
see any errors whatsoever. Seems to be doing all right.

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Now the ultimate command to
figure out if your time

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is synchronizing correctly is
by using chrony C sources.

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So here we can see the current time
sources that it is using and they are listed

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right here. And hey, there's no mention of
this dummy time server. And we don't need to

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because this dummy time server couldn't be contacted.
So you don't see it in the sources.

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We do
see a source.

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Oh, that's a
stratum one fancy.

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So 192192630 stratum one most reliable.
And you can also see that the

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difference between the local clock and
this remote clock is really minimal.

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It's also in touch with a couple of other time
servers, which is helpful in case you lose contact with the

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Stratum 1 server. Then it has a fallback for other
servers. That's how you use time synchronization on Red Hat.