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In this demo, we are going to demonstrate the use

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of Volumes which we have discussed in the theory.

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Let's start with creating the Volume which we had

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deleted in the last demo, which is vol-ubuntu.

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We will do it by running a container from ubuntu image called cont-ubuntu.

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[No Audio]

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Let's see if both the Volume and the container are available.

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Again, to remind you, we can always check the

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container using docker container inspect command

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and find the information about Volume by formatting its output.

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As you can see, the container called cont-ubuntu

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has the Volume vol-ubuntu attached to it.

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Now, let's execute our container

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and run bash command on it.

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You can notice that we are not executing it as a daemon container,

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which means that once this command succeeds,

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we will jump right into the terminal of our container.

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Right now, this container is in its

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default state, which means that even if we delete it

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and spin it up, again, nothing will change.

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So let's make a few changes to it, which will be

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reflected in its read-write topmost layer.

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And if we delete the container, then the changes we have

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made now, would be lost. The action can be pretty

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simple here, we don't need to do something so heavy.

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Even a simple act of just updating the OS

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can create enough changes to be recognized.

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So let's update this Ubuntu by typing apt-get update command.

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Once it is updated, let's change our

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working directory to var-log. As you may

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have guessed, this is the directory where ubuntu

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is keeping its logs.

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Let's list out the available files

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and we have a lot of log files here.

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The purpose of doing so is, to make sure that once we

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stopped the container, we should be able to see

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the same files as backup on our host machine.

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And the reason for that is when we created this container,

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we had mount this directory to our host

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using the Volume val-ubuntu.

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Let's exit the process and stop the container.

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[No Audio]

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Now, let's have the root privileges on our host machine.

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And as you can see, we are on the same working

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directory just with root privileges. Now, as we

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have seen in the theory section of Volumes,

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Docker stores the backup of Volume data,

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under var-lib-docker-volumes directory.

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So let's navigate to it and let's list

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out the content in this directory. As you can see,

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we have directories of all of the Volumes created

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by local Volume driver. Now let's navigate to

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va-ubuntu to see if the changes in the log

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file are reflected. Once we are in vol-ubuntu directory,

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let's see its contents, and what we have is a data directory.

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Once we navigate to that, and list its contents

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what we see is a long list of log files,

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which means that the mounting

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of Volume with the container was successful.

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So this is how we mount a Volume to a

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container and create a backup of its data to host

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using local Volume driver