Recommended backup solution for Linux

George_Hegland

No specific distro in mind, just wondering what you'd recommend. I'm also interested in pros and cons for the alternatives, open source software is preferred, open protocols too. Best would be to use standardized file formats so that a backup file can always be recovered without depending on additional software.

Alan_Rowell

Arch wiki has the answer as usual: https://wiki.archlinux.org/title/Full_system_backup_with_tar

Here's a example script using tar:

#!/bin/bash
# full system backup

# Backup destination
backdest=/opt/backup

# Labels for backup name
#PC=${HOSTNAME}
pc=pavilion
distro=arch
type=full
date=$(date "+%F")
backupfile="$backdest/$distro-$type-$date.tar.gz"

# Exclude file location
prog=${0##*/} # Program name from filename
excdir="/home/<user>/.bin/root/backup"
exclude_file="$excdir/$prog-exc.txt"

# Check if chrooted prompt.
echo -n "First chroot from a LiveCD.  Are you ready to backup? (y/n): "
read executeback

# Check if exclude file exists
if [ ! -f $exclude_file ]; then
  echo -n "No exclude file exists, continue? (y/n): "
  read continue
  if [ $continue == "n" ]; then exit; fi
fi

if [ $executeback = "y" ]; then
  # -p, --acls and --xattrs store all permissions, ACLs and extended attributes. 
  # Without both of these, many programs will stop working!
  # It is safe to remove the verbose (-v) flag. If you are using a 
  # slow terminal, this can greatly speed up the backup process.
  tar --exclude-from=$exclude_file --acls --xattrs -cpvf $backupfile /
fi

AndrewLowrance

You can always use tar to archive a bunch of files:

tar cf archive.tar file1 file2 dir1/ dir2/ ...

c = compress and f= files. Then encrypt with AES256, using symetric key file encryption:

gpg --symmetric --cipher-algo AES256 --batch --passphrase-file /path/to/key/file archive.tar

And finally upload the encrypted archive to a object storage bucket

aws s3 sync --profile PROFILE --delete archive.tar.gpg s3://BUCKET

Donald_Alcorn

Just a heads up. Syncthing v1.16 seems to have added a long awaited feature with "untrusted devices". You can set a password, preferably a long one on a shared folder and the files will be encrypted on the remote host, the untrusted one.

https://docs.syncthing.net/users/untrusted.html

AndrewLowrance

Donald_Alcorn That does look like a great option nowadays, always been worried to store files unencrypted on public cloud servers so this is a welcome addition.

Frederik_Madsen

I would probably go for syncthing as well. Archives takes up a lot of cpu cycles and large archives are not really useful if you often take backup of the data. Once per month maybe, but with shorter interval you'd only want to copy whatever has changed.

AndrewLowrance

Frederik_Madsen Tested over the summer, best backup solution I ever had. Secure and reliable.

Frederik_Madsen

AndrewLowrance Thanks for input, made a syncthnig node for myself too.