This page shows how to define environment variables when you run a container in a Kubernetes Pod.
You need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster. If you do not already have a cluster, you can create one by using Minikube.
When you create a Pod, you can set environment variables for the containers
that run in the Pod. To set environment variables, include the env
field in
the configuration file.
In this exercise, you create a Pod that runs one container. The configuration
file for the Pod defines an environment variable with name DEMO_GREETING
and
value "Hello from the environment"
. Here is the configuration file for the
Pod:
envars.yaml |
---|
|
Create a Pod based on the YAML configuration file:
kubectl create -f http://k8s.io/docs/tasks/configure-pod-container/envars.yaml
List the running Pods:
kubectl get pods
The output is similar to this:
NAME READY STATUS RESTARTS AGE
envar-demo 1/1 Running 0 9s
Get a shell to the container running in your Pod:
kubectl exec -it envar-demo -- /bin/bash
In your shell, run the printenv
command to list the environment variables.
root@envar-demo:/# printenv
The output is similar to this:
NODE_VERSION=4.4.2
EXAMPLE_SERVICE_PORT_8080_TCP_ADDR=10.3.245.237
HOSTNAME=envar-demo
...
DEMO_GREETING=Hello from the environment
To exit the shell, enter exit
.