Kubernetes Dashboard Certs: A Comprehensive Guide

Kubernetes Dashboard is a popular web-based user interface for managing Kubernetes clusters. It provides a visual way to interact with your cluster, view resources, and perform various administrative tasks. Security is of utmost importance when using the dashboard, and one crucial aspect of securing it is the use of certificates. Kubernetes Dashboard certificates (certs) are used to establish secure communication between the client and the dashboard, ensuring data integrity and confidentiality. In this blog post, we will explore the core concepts, typical usage examples, common practices, and best practices related to Kubernetes Dashboard certs.

Table of Contents

  1. Core Concepts
  2. Typical Usage Example
  3. Common Practices
  4. Best Practices
  5. Conclusion
  6. References

Core Concepts

What are Certificates?

Certificates in the context of Kubernetes Dashboard are digital documents that verify the identity of the dashboard server and the client. They are based on the Public Key Infrastructure (PKI) system. A certificate typically contains information such as the name of the entity (e.g., the dashboard server), its public key, and the digital signature of a trusted third - party called a Certificate Authority (CA).

Why are Certificates Important for Kubernetes Dashboard?

  • Security: Certificates ensure that the communication between the client and the dashboard is encrypted. This prevents eavesdropping and man - in - the - middle attacks, where an attacker could intercept and modify the data being transmitted.
  • Authentication: They help in authenticating the identity of the dashboard server. When a client connects to the dashboard, it can verify the server’s certificate to ensure that it is communicating with the legitimate dashboard server.

Types of Certificates Used in Kubernetes Dashboard

  • Self - Signed Certificates: These are certificates that are signed by the entity that owns them. They are easy to generate but are not trusted by default by browsers or other clients because there is no third - party verification.
  • CA - Signed Certificates: These certificates are signed by a trusted Certificate Authority. Browsers and other clients have a list of trusted CAs, so CA - signed certificates are automatically trusted, providing a higher level of security and authenticity.

Typical Usage Example

Generating Self - Signed Certificates

The following steps show how to generate self - signed certificates using OpenSSL:

# Create a private key
openssl genrsa -out dashboard.key 2048

# Create a Certificate Signing Request (CSR)
openssl req -new -key dashboard.key -out dashboard.csr -subj "/CN=kubernetes-dashboard"

# Generate the self - signed certificate
openssl x509 -req -in dashboard.csr -signkey dashboard.key -out dashboard.crt -days 365

Deploying the Dashboard with Custom Certificates

  1. Create a Kubernetes secret to store the certificates:
kubectl create secret generic kubernetes-dashboard-certs --from-file=dashboard.crt --from-file=dashboard.key -n kubernetes-dashboard
  1. Modify the Kubernetes Dashboard deployment to use the custom certificates. Edit the deployment YAML file and add the following volume and volume mount:
apiVersion: apps/v1
kind: Deployment
metadata:
  name: kubernetes-dashboard
  namespace: kubernetes-dashboard
spec:
  template:
    spec:
      containers:
      - name: kubernetes-dashboard
        volumeMounts:
        - name: kubernetes-dashboard-certs
          mountPath: /certs
      volumes:
      - name: kubernetes-dashboard-certs
        secret:
          secretName: kubernetes-dashboard-certs
  1. Apply the changes:
kubectl apply -f dashboard-deployment.yaml

Common Practices

Using a Certificate Authority (CA)

Using a CA - signed certificate is a better practice than using self - signed certificates. You can obtain a CA - signed certificate from a public CA such as Let’s Encrypt or a private CA within your organization. To use a CA - signed certificate, you need to follow the CA’s procedures for certificate issuance, which usually involve domain verification.

Managing Certificate Lifecycle

Certificates have an expiration date. It is important to monitor the expiration dates of your Kubernetes Dashboard certificates and renew them before they expire. You can use tools like Cert - Manager, which is a Kubernetes add - on that automates the management and issuance of TLS certificates from various issuing sources.

Best Practices

Regular Certificate Rotation

Regularly rotating your certificates helps in maintaining security. Even if a certificate is not close to its expiration date, rotating it periodically reduces the risk of a compromised certificate being used for an extended period. You can set up a schedule for certificate rotation, for example, every 90 days.

Securing Certificate Storage

The private keys associated with the certificates are highly sensitive. They should be stored securely. In Kubernetes, you can use secrets to store the certificates, but you should also ensure that access to these secrets is restricted to authorized personnel only. Additionally, consider using encrypted storage for the secrets, especially in a multi - tenant environment.

Conclusion

Kubernetes Dashboard certs are a critical component for securing the communication between the client and the dashboard. Understanding the core concepts, typical usage examples, common practices, and best practices related to these certificates is essential for intermediate - to - advanced software engineers. By following the best practices such as using CA - signed certificates, managing the certificate lifecycle, and rotating certificates regularly, you can ensure the security and integrity of your Kubernetes Dashboard.

References