Linux backup home directory daily.

backup.sh

#!/usr/bin/env bash
#
# Backup home directory
#
#

set -o errexit
set -o nounset
set -o pipefail

readonly SOURCE_DIR="/home/joshua"
readonly BACKUP_DIR="/mnt/sega0/backups/home"
readonly DATETIME="$(date '+%Y-%m-%d_%H-%M-%S')"
readonly BACKUP_PATH="${BACKUP_DIR}/${DATETIME}"
readonly LATEST_LINK="${BACKUP_DIR}/latest"

if [ "$EUID" -ne 0 ]; then
  echo "Please run as root"
  exit 1
fi

mkdir -p "${BACKUP_DIR}"

rsync -ahv --progress --delete \
  "${SOURCE_DIR}/" \
  --link-dest "${LATEST_LINK}" \
  --exclude=".cache" \
  --exclude=".cpan" \
  --exclude=".npm" \
  --exclude=".vim" \
  --exclude=".vscode-server" \
  "${BACKUP_PATH}"

rm -rf "${LATEST_LINK}"
ln -s "${BACKUP_PATH}" "${LATEST_LINK}"

home-backup.service

# /etc/systemd/system/home-backup.service
[Unit]
Description=Backup entire user home directory to other disk.
After=network-online.target

[Service]
Type=oneshot
WorkingDirectory=/home/joshua/auto_backup
ExecStart=/bin/bash /home/joshua/auto_backup/backup.sh
RemainAfterExit=False
StandardOutput=journal

[Install]
WantedBy=multi-user.target

home-backup.timer

# /etc/systemd/system/home-backup.timer
[Unit]
Description=Backup home directory daily.

[Timer]
OnCalendar=daily
Persistent=true

[Install]
WantedBy=timers.target