Production Secrets Management in Thanos

Thanos does not have a built-in secrets management feature. However, it relies on external secret management solutions to protect and manage sensitive information, such as passwords, API keys, and configuration details. Below are recommended practices and examples for implementing secrets management in a Thanos production environment.

External Secrets Management Solutions

1. Kubernetes Secrets

   • When deployed in a Kubernetes environment, Thanos can leverage Kubernetes Secrets to store sensitive data. Kubernetes Secrets are base64 encoded, and it is crucial to configure necessary RBAC permissions to limit access.

   Example: Creating a Kubernetes Secret

   kubectl create secret generic thanos-secrets \
       --from-literal=type=secret_value \
       --from-literal=password=mysecretpassword
   

   You can reference this secret in your Thanos deployment YAML file.

   Example: Referencing Secrets in Deployment

   apiVersion: apps/v1
   kind: Deployment
   metadata:
     name: thanos
   spec:
     template:
       spec:
         containers:
         - name: thanos
           image: thanos:latest
           env:
           - name: MY_SECRET_PASSWORD
             valueFrom:
               secretKeyRef:
                 name: thanos-secrets
                 key: password
   

2. HashiCorp Vault

   • HashiCorp Vault is another widely-used solution for managing secrets. You can integrate Thanos with Vault by employing a sidecar container that retrieves secrets on startup.

   Example: Configuring Thanos with Vault

   apiVersion: apps/v1
   kind: Deployment
   metadata:
     name: thanos
   spec:
     template:
       spec:
         containers:
         - name: thanos
           image: thanos:latest
           env:
           - name: VAULT_ADDR
             value: "http://vault:8200"
           - name: VAULT_TOKEN
             value: "your-vault-token"
   

   Thanos can access the secrets stored in Vault at runtime through environment variables or configuration files.

Configuration Best Practices

• Use Environment Variables: When configuring Thanos, avoid hardcoding secrets. Instead, use environment variables that reference the secrets retrieved from your management solution.

  Example: Accessing an Environment Variable in Configuration

  In a YAML configuration file (e.g., thanos.yaml):

  objstore:
    config:
      type: SWIFT
      auth:
        username: "${SWIFT_USERNAME}"
        password: "${SWIFT_PASSWORD}"
  

• Minimal RBAC Permissions: When using Kubernetes, apply the principle of least privilege for RBAC permissions for the Thanos components. Only provide access to the secrets necessary for the functionality required.

Testing with Secrets

Testing can be orchestrated to ensure that Thanos behaves as expected with the secrets loaded from your chosen management method. The project contains specific build constraints for testing with files that might include sensitive configurations.

To test that your changes work alongside secrets but exclude certain platforms or configurations during testing, you can run:

go test -tags '!linux,!stringlabels'

This will exclude tests that should not run in your environment, allowing you to validate deployment without exposing sensitive information.

Conclusion

By leveraging Kubernetes Secrets or HashiCorp Vault, you can ensure that Thanos effectively manages production secrets. Following best practices for configuration and permissions will enhance the security posture of your Thanos deployment. While the management of secrets is outside the scope of Thanos itself, integration with external tools ensures the confidentiality and integrity of sensitive data.