#!/bin/bash

# This script makes a snapshot of several databases using rsync.
# It's based on Geordy Kitchen's snapshot script found at mikerubel.org
# which was based on Rob Bos's snapshot script found at mikerubel.org.

# You will need to have ssh keys set up to allow access witout password


# Version 0.1, Darrel O'Pry, April 18, 2003

# This script is released under the terms of the GNU General Public License,
# version 2.0.

# Your crontab will typically look something like this:
# 0 */4 * * * /bin/this_script hourly
# 59 3 * * * /bin/this_script daily
# 58 3 * * 0 /bin/this_script weekly
# 57 3 1 * * /bin/this_script monthly

# Configuration

# Destination directory.
dst=/backup/db

remoteserver="server.com"

  # Use a trailing slash for directories, just the filename for files.
database="database1 database2"

  # Number of times to run per day.
hourly=1

# Constants
daily=7
weekly=4
monthly=12

MOUNT_DEVICE=/dev/hda3
SNAPSHOT_RW=/backup

date

# attempt to remount the RW mount point as RW; else abort
mount -o remount,rw $MOUNT_DEVICE $SNAPSHOT_RW ;
if (( $? )); then
{
        $ECHO "snapshot: could not remount $SNAPSHOT_RW readwrite";
        exit;
}
fi;



case $1 in
    hourly)
        [ -d $dst/$1.1 ] && cp -al $dst/$1.1 $dst/$1.0
        for i in $database; do
            [ -d $dst/$1.0/$i ] || mkdir -p $dst/$1.0/$i
            ssh $remoteserver mysqlhotcopy -p xxxx --allowold $i /root
            rsync -e ssh -a --delete $srcroot:/root/$i $dst/$1.0/
        done
        ;;
    daily)
        [ -d $dst/hourly.$hourly ] && mv $dst/hourly.$hourly $dst/daily.0
        ;;
    weekly)
        [ -d $dst/daily.$daily ] && mv $dst/daily.$daily $dst/weekly.0
        ;;
    monthly)
        [ -d $dst/weekly.$weekly ] && mv $dst/weekly.$weekly $dst/monthly.0
        ;;
    *)
        echo "syntax: $0 <type>"
        exit 1
        ;;
esac

# Rotate the current list of backups, if we can.
if [ -d $dst/$1.0 ]; then
        oldest=`ls -d $dst/$1.* | tail -n 1 | sed 's/^.*\.//'`
        for i in `seq $oldest 0`; do
            mv $dst/$1.$i $dst/$1.$((i+1))
        done
fi

# if we've rotated the last backup off the stack, remove it.
[ -d $dst/$1.$((${!1}+1)) ] && rm -rf $dst/$1.$((${!1}+1))

# finally, let's make the new snapshot reflect the current date.
[ -d $dst/$1.1 ] && touch $dst/$1.1

mount -o remount,ro $MOUNT_DEVICE $SNAPSHOT_RW ;
if (( $? )); then
{
        $ECHO "snapshot: could not remount $SNAPSHOT_RW readonly";
        exit;
} fi;