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So friends, now that we know how to format a file system on our devices using

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Ansible,

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what we now want to do is to be able to access that data on those file systems.

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The key point here to do this is to ensure that we actually mount that file

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system.

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So with that said, let's talk about some of the key concepts behind file

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mounting.

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So one of the cool things about Linux is as you happen to traverse across

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different directories,

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you can actually be transparently moving across different devices on the system
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you can actually be transparently moving across different devices on the system

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.

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What do I mean when I say that? I'll say for example, we have a disk right here

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.

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And let's maybe add a second disk right here. I know I know my artistic skills

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are not quite so

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good, but nevertheless, let's imagine these are two hard disks. Okay. So let's

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imagine that we go

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into the home directory, you know, just by typing the command cdhome. And let's

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say for example,

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we're actually accessing data on this disk right here. Now we don't have to

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worry about how this

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disk is actually partitioned, whatever it may be. Let's just look at this at a
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disk is actually partitioned, whatever it may be. Let's just look at this at a

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high level. We're

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accessing this particular disk. Now, what if we then type the command, well, I

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don't know,

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let's go with cd/bin. Now it is completely plausible that we will still be

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accessing information on

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the same disk depending on how the device is configured. However, what might

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actually happen

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is well, you just see a change on the command line. You know, you're no longer

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in the home directory

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or in the bin directory. You could potentially be accessing an entirely
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different disk completely.

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Now the way this is actually made possible, it's all down to how these

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partitions happen to be

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mounted. Pretty much when you have a partition that has been formatted, you can

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specify a particular

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mount point where you want that particular file system to be accessible from.

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Now realistically,

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this is what I want to talk about in this particular video. So one of my

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favorite commands in order

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to determine whether or not a device happens to be mounted is to use the
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to determine whether or not a device happens to be mounted is to use the

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command lsblk-f.

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So what we actually see here is we see the name of the device as well as the

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file system type.

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We get information relating to its label as your ID as well as how much of the

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file system is

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available and how much of it is actually in use. Now more crucially though,

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relevant to what we

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are talking about is on the very right hand side, we have this option here,

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mount points. This tells

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us where that particular partition happened to be mounted, i.e. where it

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happens to be accessible.

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Check this out right here. Take for example, my XFS file system right here, my
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Check this out right here. Take for example, my XFS file system right here, my

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main file system.

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This happened to be mounted in the root directory. Whereas we also happen to

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have a separate partition,

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which is again, XFS base, but this is going to be my boot partition and it's

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actually on a separate

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partition, you see that. Now this is not the only command we can use to see

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such information.

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We can also type the command mount and that is going to give us all the

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information

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about these mounted devices. And if I wanted to perhaps be great for a

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particular piece of

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information, I could say grep nvm e. Check this out right here, we have two
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information, I could say grep nvm e. Check this out right here, we have two

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entries. Here is the

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first one and we can see the device is disc number one. This is partition

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number two and this is

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mounted on the boot directory. We can see the type is XFS and then we also have

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some information

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about the disk itself. It happens to be read rateable as well as a whole bunch

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of other information.

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Similarly, we also have this partition right here, n1p1, this is disc1

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partition 1,

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this is mounted on boot efi and it is formatted with a type vfat. Now this
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this is mounted on boot efi and it is formatted with a type vfat. Now this

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command doesn't just

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show me what type of mounts we have configured. We can also use this command to

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actually mount

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a particular file system. So let me go to one of my devices right here. Let's

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go into the yellow

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box right now. If I do an ls blk - if we can see here, we actually have this

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new disk which I have

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created the n2 disk. It has been formatted with the ext4 file system, but look

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at the right hand

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side, we do not have a mount point. That means we cannot access any data that
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side, we do not have a mount point. That means we cannot access any data that

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might be potentially

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written on this particular partition, nor can we actually write any new data to

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it. So let's say

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I wanted to actually create a mount point. What I actually want to do is I want

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to make sure that I

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have an existing directory that says very, very important. And ideally, we

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really want that directory

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to be empty. Now there is a reason for this. Let me show you why. Let's say for

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example, I happen

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to create this directory here called, I don't know, let's call this test there.

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Okay. Now inside of
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Okay. Now inside of

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tester, if I happen to create a file, let's just call this important dot txt

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and I just go into

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insert mode and say this is some really important file. Okay, so let's imagine

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this is some really

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important data inside this file. Check this out. If I happen to try to mount a

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particular file system,

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so I say pseudo mount, I will say dash t to specify the type of the file system

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. And in fact,

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let me just double check if I don't LSB okay dash f we can see we have an ext4

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based file

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system for this particular device right here, the n2. If I say pseudo mount
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system for this particular device right here, the n2. If I say pseudo mount

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dash t ext4, and then I

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target the actual device which is nvme 0n2. And I specify that I want to mount

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it in the test

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directory. If I enter, I type in my super user password. And now if I do an LS,

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if I go into the

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tester directory and list it, what do you notice? Do you see that the important

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text file is

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suddenly inaccessible? So pretty much when we mount into a directory that
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suddenly inaccessible? So pretty much when we mount into a directory that

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already has a file in it,

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the existing contents within that directory are going to be inaccessible. But

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if I do an LSBLK

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dash, if we do see indeed that this particular file system has been mounted in

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this particular

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directory structure. Now if I want to unmount that, I can say pseudo you mount

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and then specify the

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name of the mount point of ISO wish, which is in my case here tester. So I'll

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just hit enter. Now

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we are unmounted if I list the information once again, now we are no longer

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mounted. Now notice if
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mounted. Now notice if

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I try to mount and a directory which is not already created, let's just see a

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targeted device nvme 0n2

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once again. And let's maybe say I wanted to mount it and in all the directory,

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let's call this

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test.dirtu, which doesn't actually exist. If I hit enter, it just says here

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that the mount

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point does not exist. So make sure that it does exist. And ideally, like I say,

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if I just create

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it and I make sure it's empty, if I now try to remount to an LSBLK dash, if I

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have mounted in

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this particular directory and if I so wish now what I can do, I can go into t
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this particular directory and if I so wish now what I can do, I can go into t

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ester to the vim

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file 1.txt, going to insert mode and just say now I can write data to this. So

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if I just write

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and quit, if I can't file check this out right here, we have successfully

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written to the partition

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which has been formatted with the ext4 file system because the data is now

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accessible via

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its mount point right here. So this is the process that we want to be able to

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automate using Ansible.

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So how about we check out one of the modules that we can use in order to
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So how about we check out one of the modules that we can use in order to

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perform this particular task.