WEBVTT

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Let's go over the solution
for the labs on pods.

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In this lab,
we're going to get familiar with pods.

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The first question is,
how many pods exist on the system?

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Now, we know that we can get the information

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about pods using the kubectl
get pods command.

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That's what we learned.

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We're going to run
the kubectl get pods command.

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You can ignore this line here that says

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in the current(default) namespace.

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We're going to talk about namespaces
in one of the upcoming lectures.

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You don't have to worry about that for now.

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This is for those who already
know what a namespace is.

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If you know, then just make
sure you're checking the number

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of pods in the current default namespace.

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When we're on the kubectl get pods
command, we see the result is zero.

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There are no resources found.

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We're going to select zero here.

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The next is a task.

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We've got to create
a new pod with the Nginx image.

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To create a pod, the easiest way
is to run the kubectl run command

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and we specify the image.

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We have to specify a name and an image.

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If you're not sure about the syntax,
run the help command.

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We see the name of the pod
followed by the image.

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This format.

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We're going to run that.

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Kubectl run.

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Since there's no specification
about the name of the pod,

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so we could basically name it anything,

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but the image name has to be the Nginx.

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The pod is created.

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Okay. Now, how many pods are created now?

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We've created a few more pods,
so please check again.

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Let's run kubectl get pods command.

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In addition to the Nginx
pod that we created,

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there are a few other pods
that were created by us, basically.

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There are, in total, one, two,
three, four pods at the moment.

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Let's select four.

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What is the image used
to create the new pods?

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You must look at one of the new pods
in detail to figure this out.

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Let's pick one of the pods.

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This one.

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We already know
that to look at it in detail,

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we've got to run the kubectl describe [?].

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Now we have additional
details about the pod.

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This is the name of the pod.

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You have the start time
and a number of other details.

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The question is, what is the image
used to create the new pods?

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We know that this tells us the containers.

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Here you have the image
and the image is BusyBox.

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Let's select BusyBox.

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Now, which nodes are these pods placed on?

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You must look at all the pods
in detail to figure this out.

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One way to do this is we've already run
the kubectl describe pod command,

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and we can see
that this is on node control plane.

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We could actually run the describe
command against each pod.

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That's one way to figure that out.

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Another way and an easier
way is to just run kubectl

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get pods command with the wide option.

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Here you get to see the node,
and it says control plane.

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All of the new pods are created
on the control plane node.

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Select control plane.

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How many containers
are part of the pod webapp?

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There's a new pod created.

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This one.

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Get pods command to see webapp.

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If you look at this column right here,

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it shows us the total number
of containers part of the pod.

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This number right here
is the total number of containers.

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That's one way to figure that out,
or we always run the describe command.

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To see that in detail,
here you see containers,

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then you have one container here,
it's Nginx,

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and the other one right here.

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Those are the two containers.

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We select two.

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Then you have, what images
are used in the new webapp pod?

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You must look at all the pods
in detail to figure this out.

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Actually, it should be, you must look
at all the containers. in detail.

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Here you have two containers.

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If you look here,
you see that the image for nginx is nginx,

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and the one for agentx is called agentx.

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There's nginx and agentx.

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Those are the images
used for those containers.

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This one.

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Now, what is the state of the container
agentx in the podweb app?

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If you look at the container here,
and you see there is a state

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and it is in a waiting state at the moment.

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Out of these, it's not running,
ready, or success,

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it's actually error or waiting.

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This is the state.

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Now, why do you think the container agentx

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in podweb app
is in an error or waiting state?

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Try to figure it out
from the event section of the pod.

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If you look at one of the section
here under state,

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you have the reason
called as error image pull,

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or if you just look at it below here
in the event section,

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you can see the error,
which is basically this one.

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It says, "Failed to pull image

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agentx@docker.io/libraries/agentx."

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This image by the name agentx does not exist

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and that's basically
the reason that is failing.

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The correct answer is a Docker image with

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this name doesn't exist on Docker hub.

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Now, what does
the ready column in the output

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of the kubectl get pods command indicate?

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If you go up here, we have the output
of the get pods command.

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Here you see you have 1/1 here,
and then you have 1/2.

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What does this mean?

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Now, we know that

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this is the total containers within the pod,

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and this is basically, of course,
the ones that are ready.

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At the moment,
there's only one ready out of the two,

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and we know
that because this image does not exist.

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Of course,
that's why that container isn't ready yet.

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It's basically the total containers
that are ready/just

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the total containers within the pod.

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That's total containers
in the pod or running containers

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in the pod/total containers in the pod.

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That's the correct answer.

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The next task is to delete the webapp.

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Let's run the kubectl delete
command and delete the webapp pod.

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Okay. That's deleted.

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Let's go to the next one.

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Create a new pod with the name
redis and with the image redis123.

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The recommendation is to use
a pod definition YAML file,

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and the image name is wrong.

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Yes, the image's name is wrong.

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We could do this in two ways.

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As we know,
we could run the kubectl run command.

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The name of the pod is redis,
and the name of the image is redis123.

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You could basically
just create it like this,

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but we just want to get familiar
with generating the YAML file

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and creating it with
the pod definition file.

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Let's use the dry run option

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and output

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the commands in a YAML format.

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This is basically a command and it says

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the dry run command is deprecated

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and is replaced with
the dry run equals client.

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Let's run that.

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This is the YAML file.

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Let's direct it to a file.

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We'll call it redis.yaml.

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We have the YAML definition
for that pod and this file,

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so we're now going to create
the pod using the kubectl create

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or apply command.

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Let's go with the create command.

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Okay. It's created.

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Let's verify that it's created.

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It's created and it's in an error
image pull state

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because we have the wrong image name.

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Let's click on check.

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Okay, it's successful.

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The last question for this lab

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is to change the image on this pod to redis,

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to fix that error
that we purposefully created,

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and to get the pod in a running state.

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Again, there are two ways to do that.

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You could run the kebectl
edit command to edit the pod,

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or since we already
have the redis file we could jut go in

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and change the file we created.

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Let's go and do that.

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I've changed the image name.

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I'm just going to apply the changes.

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Let's check redis.

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We'll talk about this error message later

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when we talk about imperative commands

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and the declarative way that we apply.

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For now, let's stick to the basics

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and let's just make sure
the change was successful.

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When you're on the kubectl get pods command,

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we see that the pod is in a running state.

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I'll check.

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All right.

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That's the end of the lab.

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Let's hit the end lab button.

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I'll see you in the next one.