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In this video, you'll get a quick introduction to setting up Ansible for configuration management.

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Let's first talk about the requirements. There is a control host. That is where you are going

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to push the desired state to the managed machines. And a control host, I would say you send to

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a stream or similar, but the control host can be anything nowadays. Ansible control

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hosts run successfully on any Linux distributions, on Windows, on Mac OS. But as Ansible is owned

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by Red Hat, integration is probably easier on Red Hat based distributions. Also on the

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control host, you need to set up hostname resolving for all managed nodes, unless you

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want to contact these nodes by IP address. And you generate SSH keys and copy over to

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the managed host to make sure that your current Ansible user on the control host can connect

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to the managed host without any issues. And next you install the Ansible software. You

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create an inventory file, and that's about it. Then on the managed host, you ensure that

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Python is installed. That shouldn't be a big deal nowadays, as Python is a part of the

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minimal Linux configuration. All Linux distributions, except for the very minimal cloud-based distributions

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have Python on board. You need to enable SSH access. And you need to make sure that you

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have a user with sudo privileges. If you want to make it easier, and that's what we are

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going to do here, that should be a passwordless sudo privileges. But don't worry, in order

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to use Ansible, you can do it a secure way as well and make sure that passwords are used

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in order to push the configurations. So how do we set up Ansible? Well, on the managed

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host, like Ubuntu for instance, you need to make sure that you install open SSH server.

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And then on the control host, you install the Ansible core package. You make sure that

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you have your host name resolution set up. You generate some SSH keys, copy that key

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for the same user to the managed machine, and then you update your inventory. And then

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it's time for the first command, which could be Ansible ubuntu minus mping, which is using

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the ping module, which is an Ansible module. Ansible is doing its work by using modules.

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Minus i inventory is using the inventory. Minus use student is using your student user,

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which should be the current user in this example. And minus uppercase K will prompt for the

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sudo password. Let me show you. So here I have the Ubuntu host that I want to use,

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and I need the IP address. It's giving me lots of information. But here you see information

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that is relevant. The IP address ends in 146. Next, I need to make sure that I do my sudo

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apt install open SSH dash server. This is an Ubuntu desktop and Ubuntu desktop does

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not have open SSH server by default. So make sure you install it. Fortunately, on server

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editions, you normally do have SSH installed. And now I'm going to set up my control host.

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In order to set up the control host, I need to be student user. I don't have to be the

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root user. First, I'm installing the Ansible package using sudo dnf install minus y ansible

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core. As a quick check, I'm using Ansible minus minus version, which is showing that this has

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installed Ansible version 2.16.14. So Ansible is installed. Next, I'm going to use sudo sh

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minus c echo 192.168.29.146. And I'm calling it Ubuntu.example.com short name Ubuntu. And I'm

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redirecting this to etc hosts. Let's use double quotes, no need to use single quotes. Now, what

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is this command doing? Well, we are running sudo. But the problem is that there's a redirect and

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the redirect causes confusion. And that is why I'm using sudo on the command sh minus c, where sh

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minus c executes the entire command including the redirect. If ever you want to use composed

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commands that have a redirect or a pipe in them, in sudo, it is wise to use sudo sh minus c and the

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entire command between double quotes. So as a result, I should be able to ping Ubuntu. So this

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proves that I can reach the Ubuntu machine by its name. Now I'm going to generate SSH keys. For this

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demo, I want to keep it simple. So I'm using my current sudo enabled user account, which is a

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student user. Ubuntu has a student user as well. So I'm using SSH keygen to generate a public private

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key pair, and then SSH copy ID to Ubuntu, which is copying my public key over to Ubuntu. I need to

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enter the password once. And now we have passwordless authentication on the remote host.

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Quick check when I use SSH Ubuntu, I'm on the Ubuntu machine using exit and I'm back. Okay, now I need to

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create a so called inventory. Echo Ubuntu greater than greater than inventory. The inventory file for

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Ansible identifies all the managed assets. So it's a pretty important file. Without an inventory file,

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Ansible only knows localhost. So Ansible doesn't use hostname resolution. When you are going to use

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an Ansible command, Ansible uses inventory to find more information about managed hosts. And now I

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can use a so called Ansible ad hoc command. Doing that using Ansible Ubuntu minus M ping minus I

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inventory. I'm using the ping module. The ping module, in fact, is a Python script that can be

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used to ping assets in Ansible. Minus I inventory is telling Ansible to use the inventory file I just

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created in my current directory. Minus you student is using the student user, which is my current user

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account. And not really necessary here. But let me show you anyway. Minus uppercase K will prompt for

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the sudo password at the other side. So there we go. Here is the become password. I'm entering it. And

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here we see the result of the Ansible ping module. So what does that mean? Congratulations, you just

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successfully ran your first Ansible command.