Root FS snapshotting script using BTRFS

rootfs-snap.sh

#!/bin/sh -e
#
# simple rootfs (/) snapshots using BTRFS

# variables
ROOT=/media/root/@

# begin script
if [ $(id --user) != 0 ]; then
  echo "script must be run as root"
  exit
fi

DATETIME=$(date --iso-8601=seconds)
DEST=${ROOT}-${DATETIME}
LOGFILE=${DEST}.log

btrfs subvolume snapshot -r ${ROOT} ${DEST}
ln --symbolic --force --relative --no-target-directory ${DEST} ${ROOT}-latest

# open log file to add description of changes
nano --tempfile ${LOGFILE}
chmod 0444 ${LOGFILE}

# sync timestamps
touch --reference ${DEST} ${LOGFILE}

exit 0