troubleshooting-devbox

Diagnose SSH host key mismatches and verify NixOS configuration on Hetzner devbox.

4|Updated Jan 15, 2026

Search Tags:#troubleshoot #diagnostics #SSH #Hetzner #NixOS #devbox #host-key

Ready to run

npx skills add https://github.com/johnnymo87/workstation --skill troubleshooting-devbox

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Please help me install this Agent Skill.
Skill: troubleshooting-devbox
Source: https://github.com/johnnymo87/workstation/tree/main/.claude/skills/troubleshooting-devbox
Command: npx skills add https://github.com/johnnymo87/workstation --skill troubleshooting-devbox

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Solves SSH connection and NixOS configuration issues on the Hetzner devbox.

Core Features & Use Cases

SSH connectivity troubleshooting: Diagnose and fix host key verification errors and connection timeouts.
NixOS verification and recovery: Validate NixOS version, perform rebuilds, and rollback generations when needed.
Devbox health checks: Provide guided commands to verify services, disk space, and system status on the devbox.

Quick Start

To begin troubleshooting, use the steps described in the skill body:

Confirm the host key: ssh-keygen -R devbox; ssh-keygen -R $(hcloud server ip devbox)
Reconnect with acceptance: ssh -o StrictHostKeyChecking=accept-new devbox
Verify environment: ssh devbox 'nixos-version' && ssh devbox 'tmux -V' && ssh devbox 'nvim --version'
Check status: ssh devbox 'journalctl -b --priority=err' && ssh devbox 'systemctl --user list-timers'
If needed, rebuild: ssh devbox 'sudo nixos-rebuild switch' and reboot as necessary.

Frequently Asked Questions about troubleshooting-devbox

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I fix SSH host key verification errors on my Hetzner devbox?▼

SSH host key errors occur when the remote host's key changes or doesn't match your local cache. Remove the old key with ssh-keygen -R devbox and ssh-keygen -R $(hcloud server ip devbox), then reconnect using ssh -o StrictHostKeyChecking=accept-new devbox to accept the new key.

What steps should I take to troubleshoot SSH connection timeouts on NixOS?▼

Verify NixOS and required services are running on the devbox using ssh devbox 'nixos-version', ssh devbox 'tmux -V', and ssh devbox 'nvim --version'. Check system errors with journalctl -b --priority=err and review active services using systemctl --user list-timers.

How do I verify my devbox setup is healthy after server recreation?▼

Run health checks to confirm environment integrity: confirm the SSH host key, verify NixOS version and tools are installed, check system logs for errors, and validate active services. Rebuild NixOS with sudo nixos-rebuild switch if needed and reboot as necessary.

Can I recover my NixOS configuration after reinitialization?▼

NixOS recovery involves rolling back to a previous generation or rebuilding your configuration. Use journalctl to identify errors, then run sudo nixos-rebuild switch to apply the current configuration, or reboot to activate changes.

What should I check if SSH connection to my devbox keeps failing?▼

Troubleshoot SSH failures by removing stale host keys, verifying connectivity with updated key acceptance, checking NixOS system health via journalctl and systemctl, and confirming disk space and service status on the remote host.