+++
date = '2025-11-03T09:31:57+01:00'
draft = false
tags = [ "homelab" ]
title = 'A little energy-conciousness'
+++

I like when things take care of themselves.  
But before you can automate backups, the machine to be backed up has to be awake.  
Pennsardin — my big desktop tower running a RAID 5 array — has an annoying tendency to sleep deeply.

Instead of leaving it powered on 24/7 just “for convenience,” I chose **energy sobriety**.  
My main server stays on, but the others only wake up when they actually have work to do —  
in this case, during nightly backups.

A short Bash script, a bit of patience, and the process flows naturally.

```bash
#!/usr/bin/env bash

MAC="00:52:54:46:58:34"
echo "[+] Waking up Pennsardin via Wake-on-LAN"
wakeonlan ${MAC}

echo "[+] Waiting for Pennsardin to respond"
until ping -c1 192.168.0.12 &>/dev/null; do
  sleep 1
  printf "."
done
echo -e "\n[+] Pennsardin is online"

echo "[+] Connecting to lomig@pennsardin ..."
exec ssh lomig@192.168.0.12
```

Here’s the idea:

1.	A Wake-on-LAN packet brings the system out of its nap.
2.	A simple loop waits for the first ping reply — making sure the machine is really awake.
3.	Finally, an SSH connection triggers the backup sequence.

This little ritual sums up my homelab philosophy perfectly:
automate without wasting.
You don’t need an always-on cluster to handle a few backups and a blog — just a bit of organization, restraint, and common sense.

Next step?
Scheduling this wake-up via systemd, and letting Pennsardin go back to sleep once the backup is done.
A digital butler — punctual and energy-conscious.