Kubernetes is a powerful tool. It can help you manage complex applications and provide you with the ability to easily automate tasks involved in managing them. In this course, we will start exploring Kubernetes from a beginner's standpoint. We will discuss what Kubernetes is and what it does, and we will work with some of the basic functionality of Kubernetes hands-on. We will build a simple Kubernetes cluster. We will also deploy a sample microservice application to the cluster in order to explore how Kubernetes can help easily manage such applications.

A Practical Guide to Kubernetes

## Creating a ConfigMap

In its purest, and probably the most common form, a ConfigMap takes a single file. For example, we can create one from the `cm/prometheus-conf.yml` file.

kubectl create cm my-config \
    --from-file=cm/prometheus-conf.yml

We created a ConfigMap (`cm`) called `my-config`. The data of the map is the content of the `cm/prometheus-conf.yml` file.
### Looking into the Description
Let's describe it, and see what we'll get.

Name:         my-config
Namespace:    default
Labels:       <none>
Annotations:  <none>

Data
====
prometheus-conf.yml:
----
global:
  scrape_interval:     15s

scrape_configs:
  - job_name: prometheus
    metrics_path: /prometheus/metrics
    static_configs:
      - targets:
        - localhost:9090

Events:  <none>

The important part is located below `Data`. We can see the key which, in this case, is the name of the file (`prometheus-conf.yml`). Further down you can see the content of the file. If you execute `cat cm/prometheus-conf.yml`, you'll see that it is the same as what we saw from the ConfigMap's description.
## Mounting the ConfigMap
ConfigMap is useless by itself. It is yet another Volume which, like all the others, needs a mount.
### Pod with Mounted ConfigMap
Let's take a look at a Pod specification defined in `cm/alpine.yml`.

# Creating a ConfigMap

In its purest, and probably the most common form, a ConfigMap takes a single file. For example, we can create one from the `cm/prometheus-conf.yml` file.

We created a ConfigMap (`cm`) called `my-config`. The data of the map is the content of the `cm/prometheus-conf.yml` file.
## Looking into the Description
Let's describe it, and see what we'll get.

The important part is located below `Data`. We can see the key which, in this case, is the name of the file (`prometheus-conf.yml`). Further down you can see the content of the file. If you execute `cat cm/prometheus-conf.yml`, you'll see that it is the same as what we saw from the ConfigMap's description.
# Mounting the ConfigMap
ConfigMap is useless by itself. It is yet another Volume which, like all the others, needs a mount.
## Pod with Mounted ConfigMap
Let's take a look at a Pod specification defined in `cm/alpine.yml`.

In this lesson, we will learn to inject configuration from a single file using the ConfigMap Volume.

Injecting Configuration from a Single File

Creating a ConfigMap

Looking into the Description