Skip to content

System Administration

Demi can monitor system resources, change system settings, and reboot the machine.

System Stats

You: what's using the most CPU?
Demi: ★ system_info (action=processes)
      Top processes: ollama (45% CPU), podman (12%), ...

You: how much memory is free?
Demi: ★ system_info (action=memory)
      Total: 4GB, Used: 2.8GB, Available: 1.2GB, Swap: 0B

You: show me disk usage
Demi: ★ system_info (action=overview)
      Disk total: 20.0 GB, Disk free: 8.2 GB (59% used)

System Settings

Changing hostname, timezone, or rebooting requires confirmation.

You: set my hostname to homelab

Demi: Setting hostname to "homelab":
      ~ networking.hostName: nixos -> homelab
      Note: certificates or DNS records referencing "nixos" may need updating.

      Ready to proceed?

You: yes

Demi: Hostname set to homelab. Rebuild complete.

You: change timezone to America/New_York

Demi: Setting timezone:
      ~ time.timeZone: Europe/Amsterdam -> America/New_York
      Note: log timestamps will shift. Containers with TZ env vars keep their own timezone.

      Ready to proceed?

Rebooting

You: reboot the system

Demi: Rebooting will temporarily take down all services:
      - postgres (port 5432)
      - nginx (port 9000)
      All services will restart automatically on boot.

      Ready to proceed?

You: yes

Demi: Reboot initiated. System is going down.

Firewall

You: what ports are open?
Demi: ★ firewall (action=list)
      Open TCP ports: 22, 80, 443, 5432, 9000, 25565

You: close port 25565
Demi: Closing port 25565. Minecraft server will no longer be reachable
      from outside. Ready to proceed?

You: yes
Demi: Port closed. Rebuild complete.

Disk Cleanup

You: how much disk space do I have?
Demi: ★ cleanup (action=status)
      Disk: 8.2 GB free of 20.0 GB (59% used)
      Nix store: 6.4G
      NixOS generations: 15
      Container images: 8
      Dangling images: 3

You: free up some space
Demi: I'll clean up dangling container images and old nix generations.
      Ready to proceed?

You: yes
Demi: ★ cleanup (action=all)
      Cleaned 3 dangling images, garbage collected 2.1 GB from nix store.
      Disk now: 12.4 GB free (38% used).

Rollback

If something goes wrong after a rebuild, roll back instantly:

You: rollback to the previous configuration

Demi: Rolling back to the previous NixOS generation.
      This will undo the last nixos-rebuild.

      Ready to proceed?

You: yes

Demi: Rolled back to previous generation.