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We've been playing around with pods and deployments for quite a while.

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And at this point in time if we do a cube GTL get pods we'll see that we still have one pod running

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from our deployment.

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So in theory this thing right here at this pod inside of it is running a container and it's inside that

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container is our post application.

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So at this point.

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Quick question for you.

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How do we actually make a request to that application somewhere hidden in all these crazy layers.

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Is our original node server.

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How do we actually make use of that thing.

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Well that's we're gonna figure out in this video.

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So we're going to be discussing services.

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Remember a service is another kind of object in Cuban settings.

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It's an object very similar to our.

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A pod is an object or a deployment is an object.

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We create services using config files just as we do.

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Pods and deployments we are going to make use of services to set up some communication between all of

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our different pods or to get access to a pod from the outside of our cluster.

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So any time we need to have some communication or networking between our pods which is the case with

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our event boss trying to send events over to our those images or the post pods or any time that we need

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to somehow access a pod from outside of the cluster we are always going to be making use of a service.

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So anytime we think of networking or communication in any way shape or form we are always thinking about

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services just about every single pod that we ever create.

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We're going to want to communicate with in some fashion.

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So just about every pod or every deployment we create is always going to have some kind of matching

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service along with it.

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Behind the scenes there are actually several different kinds of services.

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So let's go over these different types really quickly.

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There are four different types of services that we need to be aware of but effectively there's only

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two cluster HP and load balancer that we're going to be using on a very daily basis luster IP.

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Services are used anytime that we want to set up communication between different pods inside of our

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cluster node ports are used anytime they want to access a pod from outside of our cluster but we only

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usually only use a node port for development purposes load balancers are the right way to access a pod

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from outside the cluster.

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You can think of a node port and load balancer as being very similar but the way that they actually

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work are very different.

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I'll be sure to tell you exactly how they're different over time so node port and load balancer are

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both going to expose a port to the outside world.

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We expose a pod to the outside world.

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And then finally external name services.

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I only put it in this diagram so that you are aware that this exists and it is another type of service

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but it's not something that we are going to use.

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It's a very advanced very kind of corner case thing that we're not really going to worry about so quick

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question for you out of these three different types of services what would be the most appropriate type

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of service to use if we want to setup some kind of communication between these different pods.

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Well in this case we are trying to set up communication between pods inside of a cluster.

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So that would be most appropriate for a cluster IP type service because it only exposes pods to other

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pods inside the cluster.

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So we would want this right here to be a cluster IP service about the other scenario scenario in which

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we want to access a pod from the outside world like maybe a browser running are on our computer or a

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browser running on some user's machine in this scenario.

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We are trying to access a pod from the outside world so we could use either a node port or a load balancer

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if we are in a development environment and we just want to do one little quick one off test or something

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like that.

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We would use a node port but in just about every other scenario we are going to use a load balancer

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type service.

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So in this case we would make this either a load balancer

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and I'll say sorry about that.

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We would all on here at the very end or possibly a node port so those are some the different types of

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services that we're going to make use up.

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Again we're going to be mostly focused on cluster IP and load balancer but we will sometimes make use

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of no port.

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So let's take a quick pause right here.

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We're gonna come back the next video and we're gonna start to create our first service.