Part 1: Using ConfigMaps

This is Part 1 of a multi-part, self-paced quick start exercise.

Note

This exercise requires MicroK8s and uses alias kubectl='microk8s kubectl'. If you do not have these already installed and running, see "Prerequisites".

What Will You Do¶

In part 1, you will:

Use a ConfigMap to store a key-value pair.

Estimated Time

Estimated time for this exercise is 5 minutes. Watch a video of the exercise below.

Using ConfigMaps¶

A ConfigMap is an API object used to store non-confidential data in key-value pairs. Pods can consume ConfigMaps as environment variables, command-line arguments, or as configuration files in a volume.

ConfigMap YAML file¶

Create a configmap using a YAML file, which is a configuration file. You could create a YAML file from the command line, but for this exercise, you can just use a text editor. Or you can download the configmap YAML file from this public Git repository.

macOSWindowsUbuntu

Open the Terminal.
Navigate to the Downloads folder.
```
cd ./Downloads
```
Use the following command to create an empty YAML file in your Downloads folder.
```
touch configmap.yaml
```
Use the nano text editor in the Terminal.
```
nano configmap.yaml
```
Copy and paste the configuration below into the text editor.
Press Cmd + X, then type Y and press Return to save the configmap.yaml file.

Open the command prompt.
Navigate to the Downloads folder.
```
cd ./Downloads
```
Use the following command to create an empty YAML file in your Downloads folder.
```
copy NUL configmap.yaml
```
Open the configmap.yaml file with a text editor. For example, use Notepad++ to edit the YAML file.
Copy and paste the configuration below into the text editor.
Save the configmap.yaml file.

Open the Terminal.
Navigate to the Downloads folder.
```
cd ./Downloads
```
Use the following command to create an empty YAML file in your Downloads folder.
```
touch configmap.yaml
```
Use the nano text editor in the Terminal.
```
nano configmap.yaml
```
Copy and paste the configuration below into the text editor.
Press Ctrl + X, then type Y and press Enter to save the configmap.yaml file.

Add a ConfigMap¶

In the Terminal or Command Prompt, add the configmap to your environment using a YAML file.
```
kubectl create -f configmap.yaml
```
List the configmaps.
```
kubectl get configmaps
```

configmap.yaml¶

apiVersion: v1
kind: ConfigMap
metadata:
  name: mysql-config
  labels:
    app: mysql
data:
  MYSQL_DB: mysqldb