backup.sh

#!/bin/sh

set -eu

WD=/var/backups/mysql
LATEST=$WD/latest

PREVIOUS=`readlink -e $LATEST`
NEXT=$WD/`date '+%Y%m%d-%H%M'`

if [ -d "$NEXT" ]; then
        echo "\`$NEXT' already exists."
        exit 1
fi

if [ "$#" -gt 1 ] && [ "$1" = "full" ]; then
        NEXT=$NEXT-full
        xtrabackup --backup --target-dir=$NEXT 2> $NEXT.log
else
        if ! [ -L "$LATEST" ]; then
                echo "\`$LATEST' does not exists. Consider doing a full backup first."
                exit 1
        fi

        xtrabackup --backup --target-dir=$NEXT --incremental-basedir=$PREVIOUS 2> $NEXT.log
fi

rm -f $LATEST $LATEST.log
ln -s $NEXT $LATEST
ln -s $NEXT.log $LATEST.log