Kubernetes Certificate Updater (update-kube-config)

A tool to automatically update Kubernetes certificate data in your kubeconfig file by connecting to each cluster and fetching the latest credentials.

Overview

This tool helps maintain your Kubernetes configurations by:

• Scanning your ~/.kube/config file for all contexts
• Connecting to each Kubernetes cluster via SSH
• Fetching the latest certificate data from /etc/kubernetes/admin.conf
• Updating your local kubeconfig with the new credentials
• Saving SSH usernames for future use

Installation

Install with uv tool install:

uv tool install git+https://github.com/jcppkkk/update-kube-config.git

Usage

Simply run:

uvx --from git+https://github.com/jcppkkk/update-kube-config.git update-kube-config

or install the tool and run:

uv tool install git+https://github.com/jcppkkk/update-kube-config.git
update-kube-config

The tool will:

1. Create a backup of your existing kubeconfig
2. Process each context in your kubeconfig
3. Connect to each cluster's server
4. Update certificate data as needed

First-time Usage

When connecting to a server for the first time, you'll be prompted for:

• SSH username for the server
• Sudo password (if required to read admin.conf)

The SSH username is saved in your kubeconfig for future use under the cluster's serveruser field.

Security

• Creates automatic backups of your kubeconfig before making changes
• Uses SSH for secure remote connections
• Handles sudo access securely when required
• Stores credentials only in your kubeconfig file

Requirements

• Python 3.8 or higher
• SSH access to your Kubernetes clusters
• Sudo privileges on remote servers (if required)
• Read access to /etc/kubernetes/admin.conf on remote servers

Features

• ✅ Automatic certificate updates
• ✅ Multi-context support
• ✅ SSH username persistence
• ✅ Automatic kubeconfig backups
• ✅ Sudo handling when required
• ✅ Non-interactive mode after initial setup

Troubleshooting

If you encounter issues:

1. Check SSH access to your clusters
2. Verify sudo privileges if required
3. Ensure /etc/kubernetes/admin.conf exists on the remote servers
4. Check the backup file at ~/.kube/config.bak if needed

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

MIT License