#!/bin/sh
set -ex

# read day; 0 is Sunday, for zero backup level, i.e. weekly
level=`date +%w`

# overwrite level from argument, if specified
level=${1:-$level}

phase="daily"

test $level -eq 0 && phase="weekly" \
    && for i in /mnt/data/data*.xfsdump.lz4; do
        mv -f "$i" "$i.bak" || true
    done

xfs_freeze -f /data
xfsdump -l ${level} \
    -M "data backup" \
    -L "$phase" \
    -p 100 \
    - /data | lz4c - - > /mnt/data/data${level}.xfsdump.lz4
xfs_freeze -u /data

test $level -eq 0 && rm -f /mnt/data/data*.xfsdump.lz4.bak || true