Kubernetes Secrets let you store and manage sensitive information like as passwords, OAuth tokens, ssh keys, etc.

With this article, you'll learn how to use them easily.

What is a Secret in Kubernetes?

A secret is an object that contains sensitive information like passwords, keys, tokens...

To use it, a Pod needs to reference it:

• As files in a volume mounted on one or more of its containers.
• By the kubelet when pulling images for the Pod.

Optimal way to create and mount a Secret

For me the easiest way to use Secrets is defining a YAML and reference them using envFrom/secretRef.

1. Here is a yaml configuration file you can use to create a Secret that holds a username and a password:

apiVersion: v1
kind: Secret
metadata:
  name: my-secret
data:
  username: my-username
  password: vdg7JbgkdnRnN03e

2. Reference the Secret (my-secret-pod.yaml):

kind: Pod
apiVersion: v1
metadata:
  name: my-secret-pod
  namespace: my-namespace
spec:
  containers:
    - name: my-container
      image: nginx:1.7.9
      envFrom:
        - secretRef:
            name: my-secret

3. Then you just need to create the Pod:

$ kubectl apply -f my-secret-pod.yaml -n my-namespace

For more information related to Secrets, please check the Kubernetes documentation.