The danger of backing up a live System - and possibly a bigger change required to fix

[zDEFz]

I've been actively following Penguins-Eggs, and at some point, I believed it could serve as a valuable tool for creating an installer or even a live backup solution. However, the more I've used it, the more I've wished it could perform its functions without the need to mount the operating system.

Why is that? Well, there are side effects associated with the process, such as the potential for data corruption and network connectivity issues, among others.

So, what approach did I eventually adopt for my specific needs? I ended up booting into NixOS, which is installed alongside Arch Linux, and I mounted the OS partition in a read-only mode. This setup provided me with a solid foundation.

After that, I executed my backup scripts, allowed them to modify the systemd bootloader entry, and initiated a reboot. This process also served as my cronjob, and it has proven to be reliable for me, free from any adverse side effects. It backs up data into a Borg repository on another disk, effectively performing deduplication.

In addition to this, I've established an hourly backup routine for my /home/ and /root/ directories, which are stored in another Borg repository, as long as my system remains mounted.

The main point I want to emphasize is that if Penguins-Eggs continues to copy the live system as it currently does, it may lead to unresolved issues down the road.

[pieroproietti]

Hi zDEFz

I was worried to not hear news from you, so I'm really happy to read you again.

During this days I did a great work to clean various bugs in eggs, iincluding look to yours suggestions, for that I was able to do, of course.

Regarding your solution is interesting, I heard about NixOS I know it's interesting, but never used it.

Using anotherer OS to backup it not exacly a new idea, have a lot of advantages if we want to get a simple backup of our system, less if you see your system like something in continuos evolution.

eggs - the idea behing eggs - is a bit more like to get a son of the the system, not exacly a clone.

In our case, we put the variants, but the system must to be capable of reproduction alone.

Really I think eggs - I mean the idea - must to be included on the OSes to get them to evolve with time.

For where? Simply I don't know, but - at last - this is not necessary to go.

I will get a look on NixOS and I'm curious about your way, but I wasn't able to find your solution on github.

Have great time

Piero

[zDEFz]

Hey. It's really simple:

1. Make a extra partition for nixos on your current disk
2. Boot NixOS and in calamares use 'replace partition'
3. NixOS will use systemd-boot as well

What I do is to simply do my backup from there, and then overwrite the default loader entry at /boot/loader/entries/
A word of warning: Not all distributions behave like this. NixOS will keep the entries intact.

I then simply say ... sh /boot/scripts/update-loader.sh default; reboot

#!/bin/bash

gen_dir="/boot/loader/entries"

update_loader_conf() {
  sed -i "s/default .*\.conf/default $1/" /boot/loader/loader.conf
}

if [ $# -eq 1 ]; then
  case "$1" in
    "highest")
      highest_gen_file=$(find "$gen_dir" -type f -name "nixos-generation-*.conf" | sort -t '-' -k 4 -n | tail -n 1)
      if [ -n "$highest_gen_file" ]; then
        update_loader_conf "$(basename "$highest_gen_file")"
      else
        echo "No NixOS generation files found in $gen_dir"
      fi
      ;;
    "cachyos")
      update_loader_conf "linux-cachyos.conf"
      ;;
    "default")
      update_loader_conf "arch_linux.conf"
      ;;
    *)
      echo "Invalid argument. Use 'highest' to set to the highest NixOS generation, 'cachyos' to set to linux-cachyos.conf, or 'default' to set to arch_linux.conf."
      ;;
  esac
else
  echo "Usage: $0 <highest|cachyos|default>"
fi