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Hi let us understand some additional detail about pods. Already we do have

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minikube installed and we do have the kubectl client. I'm going to start a pod and

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see how I can leverage kubectl to explore the functionalities available as a part of

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pod. I do have the system where the minikube is installed and everything is

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running fine and kubectl is also very well configured. Now I'm going to start a

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sample pod and there are n number of ways to start the pod I'm going to use the

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easiest way to start the pod by providing an image name. I will use the kubectl

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run command and I will give a name of the pod and generator I will mention it as

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run pod version 1. The api what we are going to use over here don't worry

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as of now we will have a detailed discussion, this is to have little more

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understanding on the pod, so that we can explore various objects available as a

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part of kubernetes. I'm using the run command of kubectl and I'm providing

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a name and generator that is the api version and image I wanted to use is

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nginx. So the pod will get created, I'm going to use the command

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kubectl, get pods. That's going to list all the pods available as a part of the default

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namespace. Now I am introducing another terminology namespace

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namespace is nothing but a logical consolidation of objects together. I can

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create my own custom namespace or use the default namespace as of now I

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am going to use the default namespace and there is a system namespace

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already available where all the system related objects will be running within this

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system namespace. Here I do have the name of the pod and the status that is

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one pod needs to run and it's getting ready the status container it is getting

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created and it was created 8 seconds ago. Let me go ahead and list the pods

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yes, it is up and running and it did not get restarted any time from the beginning

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and it is up and running for 74 seconds. Now I can get more details about this

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particular pod by providing the command describe. kubectl describe

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pods and the name of the pod. I will have all the information about the pod in

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terms of what is the IP address in which node it is running and it's going to run in

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only one node as I do have minikube and it will be running in one single node, the IP

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address of the pod and what is the container running within it, as we

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discussed earlier one pod can have n number of containers, what is the idea of

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the container what image it is using and what is the state of that specific

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container, what are all the ports it is exposing and different parameters for that

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particular container and it is going to provide the output in yaml format

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and I do have different events in terms of how that particular pod got started what

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are all the events happened within that particular pod I can get those details. Now to have better understanding visually

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I am going to draw the pod unit over here, so what happened on top of minikube a

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pod got created, within pod a container got created, that got an IP address as

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this. So what did we do we created a pod quickly using the kubectl run command

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where the pod got created and a container is running within it. We do not

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have much control in terms of what port to expose how to label this pods and it's

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all going to be much difficult where I can go ahead and use a yaml file with

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declaratively I can define how that particular pod should behave what are all

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its properties and how to communicate with the pod using the kubectl. Let me go

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ahead and delete this specific pod and create a new pod using yaml file. I'm

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going to delete the pod, kubectl delete pod and the name of the pod. The pod is

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getting deleted. Now let me go ahead and list the pods there are no pods available

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as a part of default namespace, now let me go ahead and create a yaml file so

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that I can create the entire resources available as a part of the yaml file. I'm

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going to name the file as, I will be adding this specific yaml file as it is within the

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resources so that you can download and use it as it is. As we discussed earlier as a

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part of the yaml discussion we are going to have four important keys api version,

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kind, metadata and spec. I'm going to create an object called pod and the api

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version I'm going to use is version 1 and metadata I'm giving name of this

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particular pod that I wanted to create as nginx yaml and within specifications

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I'm going to have containers and within containers, I do have only one element

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which will have an image nginx and it will have the name nginx and I'm going

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to expose the port 80. I can get more details about the pod and it's a syntax

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within the reference of kubernetes website. I can get into the kubernetes api

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the latest version is version 1.18 within that you can get into pod v1 core, here

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I do have the information on what are all the fields it can have api version, kind

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metadata, spec and status. So here I'm going to have the spec as pod

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specifications, if I get into the pod spec I will have details on what are all fields it

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can have. The fields I'm going to have is containers and container is going to have

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detail about the container and it is going to be of type array. If I check the details

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about the container it will have information on what are all the fields it

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can have, the fields that we have is about images and what are all ports it can open

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again container port it's going to be of type array I can get into the container

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port and get the details on what are all the fields it can have. So the api is having

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the complete details on how the yaml file can be constructed and what are all

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informations or the fields it can have. So if I get into this pod nginx, I do have the

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specifications within that I had containers and I have the details about

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image, name, ports and ports going to have details about the container port

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name and other information. So that's what it's mentioned over here, container

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port name and in case if you wanted to specify the protocol or any host

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IP address to which I wanted to bind, I can mention all this information. Now I do

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have the pod definition using a yaml file, now I am going to create a pod, I will

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be using the command apply, kubectl apply and use the file, pod nginx.yaml

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The pod will get created, now let me go ahead and list the pods, kubectl get pods. So I do

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have one pod with a name nginx-yaml up and running. Let me go ahead and

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describe the pod, kubectl describe pods nginx yaml. So I will be having all the

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information about how I requested the pod to get created. So it got created

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within the default namespace and this is the IP address and it is using the image

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nginx and the port 80 is exposed from the container. So this nginx is exposing

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the port 80. In the next lecture we will see how to access this particular port and

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delete the pod using the file and what are all its advantages. So in a quick

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summary we saw how to create a pod using the run command as well as using

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the apply command and what are all its differences and how to get

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the details about the pod using the describe command.