Archive — Fleet-Wide Backup VM

A dedicated backup VM called Archive that continuously mirrors every machine's home directory (and Vault's /mnt) via rsync. The entire archive lives in a single git repository, committed on every sync. It's a parallel, independent backup system — not replacing snapshots, but layered on top of them.

Archive pulls. Nobody pushes to it. It has SSH access to every machine. No machine has SSH access to Archive. It's a one-way mirror.

Total estimated data to archive (reachable machines): ~44 GB (23 + 3.9 + 9.3 + 4.1 + 3.4). After initial sync, deltas will be small — mostly config changes and new event files.

The VM

Name: archive
Type: e2-small (2 vCPU, 2 GB RAM — needs enough for rsync + git)
Zone: us-central1-a (same zone as Vault for fast transfers)
Boot disk: archive — 10 GB pd-ssd (OS only)
Data disk: archive-mnt — 100 GB pd-ssd (mounted at /mnt)

100 GB gives us ~2x the current data with room to grow. As machines grow, we resize the disk — same as Vault.

Directory Structure on /mnt

/mnt/
├── mirrors/
│   ├── walter-20260203-1811z/        # named: {disk}-{creation-timestamp}
│   │   └── home/daniel/              # rsync of /home/daniel from Walter
│   ├── walter-jr-20260215-0900z/
│   │   └── home/daniel/
│   ├── vault-20260101-0000z/
│   │   ├── home/daniel/
│   │   └── mnt/                      # Vault also gets /mnt
│   ├── matilda-20260310-1200z/
│   │   └── home/daniel/
│   ├── jamie-20260101-0000z/
│   │   └── home/daniel/
│   └── foreman-20260101-0000z/
│       └── home/daniel/
└── .git/                             # entire /mnt is one git repo

The naming convention {disk}-{creation-date}z ensures that if a machine is destroyed and recreated, the old mirror stays and a new directory is created for the new disk. No collisions. No overwrites. History preserved.

What Gets Copied

For most machines: /home/daniel/

For Vault: /home/daniel/ AND /mnt/ (this is where all the important data lives)

Excluded: .cache/, node_modules/, .npm/, snap/, .local/share/Trash/, .venv/ — large ephemeral directories that can be recreated.

A script on Archive runs every 5 minutes via cron. For each machine in the gold file:

1. Check if machine is reachable (ssh -o ConnectTimeout=5)
2. If reachable: rsync -az --delete \
     --exclude='.cache/' --exclude='node_modules/' \
     --exclude='.npm/' --exclude='snap/' \
     --exclude='.local/share/Trash/' --exclude='.venv/' \
     {host}:/home/daniel/ /mnt/mirrors/{disk-name}/home/daniel/
3. If Vault: also rsync /mnt/ (excluding the mirrors themselves)
4. After all syncs: cd /mnt && git add -A && git commit -m "sync: {timestamp}"

The --delete flag means the mirror is an exact copy. Files deleted on the source are deleted in the mirror. But git preserves all history — so every deleted file is recoverable from git log.