#!/bin/bash

####################################

#

# Backup script with

# grandfather-father-son rotation.

#

####################################



# What to backup.

backup_files="/home /etc /root /boot /opt"



# Where to backup to.

dest="/mnt/backup"



# Setup variables for the archive filename.

day=$(date +%A)

hostname=$(hostname -f)



# Find which week of the month 1-4 it is.

day_num=$(date +%-d)

if (( $day_num <= 7 )); then

        week_file="$hostname-week1.tgz"

elif (( $day_num > 7 && $day_num <= 14 )); then

        week_file="$hostname-week2.tgz"

elif (( $day_num > 14 && $day_num <= 21 )); then

        week_file="$hostname-week3.tgz"

elif (( $day_num > 21 && $day_num < 32 )); then

        week_file="$hostname-week4.tgz"

fi



# Find if the Month is odd or even.

month_num=$(date +%m)

month=$(expr $month_num % 2)

if [ $month -eq 0 ]; then

        month_file="$hostname-month2.tgz"

else

        month_file="$hostname-month1.tgz"

fi



# Create archive filename.

if [ $day_num == 1 ]; then

    archive_file=$month_file

elif [ $day != "Saturday" ]; then

        archive_file="$hostname-$day.tgz"

else

    archive_file=$week_file

fi



# Print start status message.

echo "Backing up $backup_files to $dest/$archive_file"

date

echo



# Backup the files using tar.

tar czf $dest/$archive_file $backup_files



# Print end status message.

echo

echo "Backup finished"

date



# Long listing of files in $dest to check file sizes.

ls -lh $dest/