#!/bin/sh
 
# -------------------------------------
# Script to do incremental rsync backups
# from a central backup server
#
# 17/08/2010 - A Navalla Suiza <equipo@anavallasuiza.com> 
#
# http://snipplr.com/view/39964/backup-servers-from-a-central-backup-server/
#
# This script is freely distributed under the GPL
# -------------------------------------
 
 
# -------------------------------------
# Configuration
#
# You only should touch this section
# -------------------------------------
 
# email address to send the error mails
MAILADDR="logs@mydomain.com"
 
# user to login into servers (recommended root)
USER="root"
 
# root directory to for backup stuff
BASEBACKUP="/backup"
 
# folder name to full copy
FULLNAME="full"
 
# folder name to incremental changes
INCREMENTALNAME="incremental"
 
# days to store the incremental changes
INCREMENTALTIME=7
 
# host list to backup
HOSTS="myserver1.com myserver2.com myserver3.com"
 
# log directory
LOGS=`dirname "$(readlink -f "$0")"`"/logs"
 
# Size max in bytes to log files. After that size, log will be rotated and compressed
LOGSIZE=10000
 
# Search commands in...
export PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/bin/X11"
 
# -------------------------------------
# Functions definition
# -------------------------------------
 
echo_log () {
	if [ "$CMD_ECHO" != '' ]; then
		$CMD_ECHO "$1" >> $LOG
	fi
}
 
echo_start () {
	echo_log ''
	echo_log '----------------------------------------------------'
	echo_log "[$1] Start at: `$CMD_DATE "+%Y-%m-%d %H:%M:%S"`"
	echo_log '----------------------------------------------------'
}
 
echo_end () {
	echo_log ''
	echo_log '----------------------------------------------------'
	echo_log "[$1] End at: `$CMD_DATE "+%Y-%m-%d %H:%M:%S"`"
	echo_log '----------------------------------------------------'
}
 
do_rsync () {
	$CMD_KILLALL $CMD_RSYNC > /dev/null 2> /dev/null
 
	OPTIONS="--force --ignore-errors --delete --backup --backup-dir="$INCREMENTDIR/" --exclude /proc/ --exclude /dev/ --exclude /tmp/ --exclude /sys/ -e $CMD_SSH -avpz $USER@$HOST:/ $BASECOPY"
 
	echo_log ''
	echo_log '----------------------------------------------------'
	echo_log "$CMD_RSYNC $OPTIONS"
	echo_log '----------------------------------------------------'
	echo_log ''
 
	$CMD_RSYNC $OPTIONS >> $LOG 2>> $LOG
 
	echo_log ''
	echo_log '----------------------------------------------------'
	echo_log "$CMD_FIND $BASEINCREMENT -maxdepth 1 -type d -mtime +$INCREMENTALTIME -exec $CMD_RM -rf {} \;"
	echo_log '----------------------------------------------------'
	echo_log ''
 
	$CMD_FIND $BASEINCREMENT -maxdepth 1 -type d -mtime +$INCREMENTALTIME -exec $CMD_RM -rf {} \; >> $LOG 2>> $LOG
}
 
do_mail_error () {
	echo_log ''
	echo_log "[ERROR] Backup problem for $HOST"
	echo_log ''
	echo_log $1
 
	{ $CMD_ECHO 'Subject: [ERROR] Backup problem for '.$HOST; $CMD_ECHO $1; } | $CMD_SENDMAIL $MAILADDR
}
 
 
# -------------------------------------
# Script execution
# -------------------------------------
 
LOG="$LOGS/error.log"
 
COMMANDS="echo date sendmail awk bzip2 du find install killall mv rm rsync ssh"
 
for i in $COMMANDS; do
	exists=`which $i`
 
	if [ "$exists" = "" ]; then
		echo_log ''
		echo_log "Command $i does not exists in $PATH. Backup will be cancelled."
 
		if [ "$CMD_SENDMAIL" != "" ]; then
			do_mail_error "Command $i does not exists. Backup will be cancelled"
		fi
 
		echo_end
 
		exit 1
	fi
 
	eval "CMD_"`echo $i | tr "[:lower:]" "[:upper:]"`"='$exists'"
done
 
if [ ! -d $BASEBACKUP ]; then
	echo_log ''
	echo_log "Backup folder ($BASEBACKUP) does not exists"
 
	do_mail_error "Backup folder ($BASEBACKUP) does not exists"
 
	echo_end
 
	exit 1
fi
 
if [ ! -d $LOGS ]; then
	echo_log ''
	echo_log "Logs folder ($LOGS) does not exists"
 
	do_mail_error "Logs folder ($LOGS) does not exists"
 
	echo_end
 
	exit 1
fi
 
for HOST in $HOSTS; do
	LOG="$LOGS/$HOST.log"
 
	if [ -f "$LOG" ]; then
		if [ $LOGSIZE -lt "`$CMD_DU -s $LOG | $CMD_AWK -F' ' '{print $1}'`" ]; then
			OLD_LOG=$LOG.`$CMD_DATE "+%Y%m%d-%H%M%S"`
 
			$CMD_MV $LOG $OLD_LOG
 
			$CMD_BZIP2 -9 $OLD_LOG
		fi
	fi
 
	echo_start $HOST
 
	if [ "$HOST" = '' ]; then
		echo_log ''
		echo_log "No HOST is defined at first parameter"
 
		do_mail_error "No HOST is defined at first parameter"
 
		echo_end $HOST
 
		exit 1
	fi
 
	test=`$CMD_SSH -q -q $USER@$HOST $CMD_ECHO 1 || $CMD_ECHO 2`
 
	if [ "$test" = '2' ]; then
		echo_log ''
		echo_log "Can not connect to $HOST server"
 
		do_mail_error "Can not connect to $HOST server"
 
		echo_end $HOST
 
		exit 1
	fi
 
	ARCHIVEROOT="$BASEBACKUP/$HOST"
	BASECOPY="$ARCHIVEROOT/$FULLNAME"
	BASEINCREMENT="$ARCHIVEROOT/$INCREMENTALNAME"
	INCREMENTDIR="$BASEINCREMENT/"`$CMD_DATE "+%Y-%m-%d"`
 
	if [ ! -d $BASECOPY ]; then
		$CMD_INSTALL -d "$BASECOPY"
	fi
 
	if [ ! -d $BASEINCREMENT ]; then
		$CMD_INSTALL -d "$BASEINCREMENT"
	fi
 
	do_rsync
 
	echo_end $HOST
done