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- Okay, so in this lab,

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we need to reconfigure the httpd service.

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Now the fact is that we have already

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applied quite some configuration to httpd.

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And let's change it the nasty way.

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First, I'm going to make sure

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that we use systemctl stop httpd.

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Can't be running.

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Double checking.

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It's not running.

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Now I am going into

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/etc/systemd/system/ where we have

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httpd.service.d.

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In which there is override.conf.

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Now the httpd service,
like anything is configured

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in such a way that it's checking

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if there is an /etc/systemd/system/

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name of the service service.d directory.

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And if there is, it's going to include it.

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Now, if there is not, rm
-rf on httpd.service.d

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it's not going to include it.

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Now this is one of these
cases where you really must do

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a systemctl daemon-reload.

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Just to make sure that systemctl

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is fetching the latest configuration

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and it'll accept the fact

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that you have just removed everything.

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So what is happening if
we now use systemctl cat

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on httpd.service?

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Well, as you can see there
is just httpd.service

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and that's exactly what we want.

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We don't have any of this
additional configuration anymore.

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I mean the auto restart
option is a very nice option,

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but not if a service is
triggered by a socket

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then there shouldn't be any auto restart.

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And just for sanity reasons,

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I also kicked out the vsftpd
service that had required.

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And now we can move on
and we can make sure

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that the service is going to be triggered

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while traffic is hitting port 80.

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Now before doing so, it's nice

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if we have some configuration.

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So echo hello world >

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/var/www/html/index.html.

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That's a simple index html.

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Otherwise we are starting an httpd service

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that doesn't have any content to service

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and that doesn't make sense.

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Now let's check out if there
is any sockets that we can use.

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systemctl list-unit-files -t socket

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is showing us all the different sockets.

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And now look at that.

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We even have an httpd.socket.

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That's even better.

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Before using it, systemctl
cat on httpd.socket

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is showing us what?

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Is showing that this really
has everything that we need.

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So I'm just going to use

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systemctl enable --now httpd.socket

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to start the socket.

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And next I am going

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to access it using

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curl http://localhost,

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which is giving me hello world.

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And systemctl status httpd,

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do we see anything?

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Yeah, we see it is running

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triggered by httpd.socket.

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So this is really telling
us that it is running

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since seven seconds ago
triggered by the socket.

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And that's exactly what we wanted.

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This is what we are using sockets for.