#!/bin/bash -e

# Run this at a lower priority to avoid disrupting the rest of the system
ionice -c 3 -p $$
renice -n 19 -p $$ > /dev/null

(
# Only allow one backup to run at a time
if ! flock -n -x 200; then
	echo "Failed to get a lock!"
	exit 1
fi

# Exclude other filesystems from the backup. This leaves only the files we
# want, on the root file system, to back up.
# Also exclude other large collections of files which we don't care to save.
rdiff-backup \
	--preserve-numerical-ids \
	--exclude-sockets \
	--exclude '/home/*/tmp' \
	--include '/home' \
	--exclude '/backup' \
	--exclude '/tmp' \
	--exclude '/var/cache/apt/archives' \
	--exclude '/var/log' \
	--include '/var' \
	--exclude-other-filesystems \
	/ /backup/


# Remove old backups to free up some space
rdiff-backup -v1 --force --remove-older-than 365D /backup/

) 200>/var/run/backup

exit 0