Borg Backup script, modified from https://borgbackup.readthedocs.io/en/stable/quickstart.html#automating-backups

borg-backup.sh

#!/bin/sh

# sudo crontab -e
# * 3 * * * export BORG_PASSPHRASE=repo_passphrase; /path/to/backup.sh /path/to/repo.borg /source/folder/to/backup >> /path/to/backup.log 2>&1

# some helpers and error handling:
info() { printf "\n%s %s\n\n" "$( date )" "$*" >&2; }
trap 'echo $( date ) Backup interrupted >&2; exit 2' INT TERM

info "Starting backup"

borg create                         \
    --verbose                       \
    --filter AME                    \
    --list                          \
    --stats                         \
    --show-rc                       \
    --compression lz4               \
    --exclude-if-present .nobackup  \
    "$1"::"{hostname}-{utcnow}" "$2"
    
backup_exit=$?
    
info "Pruning repository"

borg prune                          \
    --list                          \
    --prefix '{hostname}-'          \
    --show-rc                       \
    --keep-daily    3               \
    --keep-weekly   2               \
    --keep-monthly  3               \
    "$1"

prune_exit=$?

# use highest exit code as global exit code
global_exit=$(( backup_exit > prune_exit ? backup_exit : prune_exit ))

if [ ${global_exit} -eq 0 ]; then
    info "Backup and Prune finished successfully"
elif [ ${global_exit} -eq 1 ]; then
    info "Backup and/or Prune finished with warnings"
else
    info "Backup and/or Prune finished with errors"
fi

exit ${global_exit}