[plug] Workshop Proposal: Hack on my collection of Rpi Zero W (e.g. micro backup server)

[mccabedj]

I have a proposal for a workshop. I bought a bunch of Rasberry Pi Zero Ws in bulk. They are lite but have everything you need to run them as a real Linux machine, e.g. 512MB of ram, networking (WIFI) and even micro-HDMI out if you really want. My proposal is to spend workshop(s) hacking on the Pis. In particular, I thought it would be interesting to convert them into low end backup servers. Draft proposal follows:

Raspberry Pi Zero W Backup server
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Problem statement: People tend to store data on Windows desktops. Even a Linux desktop runs a large amount of software, which may be compromised in some way. For this reason, I am investigating using a small $10+ Raspberry Pi dedicated to file backups that does not allow regular users to trash the backups. (Regular users should have read-only access to backups)

What to bring: Raspberry Pi zeros will be provided. Bringing your own USB power supply and MicroSD card will help. Also, bring a laptop to work on.

-- Server software --
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Linux only. Feel free to investigate a microkernel or Rust-based OS which may be more secure, but I guess they would be more troublesome than they are worth at this point.

Btrfs: The Btrfs filesystem allows us to take frequent snapshots and do live compression. A true write once read many filesystems may not be appropriate as it would be handy for an admin to be able to delete files.

Snapshot schedule: Crontab or Demon. Keep n minutely, hourly, daily, weekly, monthly and yearly backups. Only take a snapshot if the last snapshot differs from live data.

Deduplicate Btrfs: Btrfs allows you to deduplicate existing files. Existing software may be appropriate. Investigate and integrate, or write new.

Smart Features (optional): Fuse Filesystem that allows to download directory as ZIP etc.?

SSH, Samba: Install, integrate.

Current Status: See tiny GitHub repository https://github.com/gmatht/btrnas

-- Easy Installer --
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(Linux and Windows)

Windows users need a heterogeneous Linux backup server immune to Windows viruses even more than Linux users. (Do not install Wine).

See (and modify?) the new RPi installer. -- https://www.raspberrypi.com/software/

There are fewer MacOS machines out there. If we port to Linux and Windows, MacOS should be trivial to support for someone who has a MacOS machine to test and use.

-- Client Software --
---------------------

(Linux and Windows)

RSync not suitable for Windows? What about live sync, e.g. lsync?

Many options, e.g.: https://www.goodfirms.co/file-sync-software/blog/the-top-11-free-and-open-source-file-sync-software

Update in place to not flood the server with duplicates on a small change to a large file?

Avoid placing load on the small weak server for files that haven't changed.

Should we notify the server that a backup has been completed? It may be unnecessary complexity if we use lsync.

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John McCabe-Dansted