完全和差分备份的自动化模型

#!/bin/sh
　　#
　　#######################################
　　#
　　# TAR backup script to cover daily and weekly backups on one tape.
　　# Generic UNIX version - edit variables as required
　　#
　　# For this to work, it MUST be started on a Monday!
　　#
　　# Copyright (c) 1999, Tim Jones
　　# Permission granted for use/modification
　　#
　　# Tim Jones/Linux Magazine provide this shell script with no warranty
　　# (implied or otherwise)
　　#
　　########################################

　　DOW=`date +%w`
　　DATE=`date +%D`
　　DAY=`date +%A`
　　DEVICE="MY REWIND TAPE" # Rewinding tape drive
　　NDEVICE="MY NO_REWIND TAPE" # non-rewinding tape drive
　　REWIND="mt -f $DEVICE rewind"
　　EOD="mt -f $NDEVICE eod"
　　FSF="mt -f $NDEVICE fsf"
　　MAILLIST="root" # list of users to receive backup notice

　　if [ $DOW = "6" ]
　　then
　　# This is Saturday, so append and write the whole system!
　　$EOD
　　echo $DATE > /tmp/.LASTFULL
　　tar -cvvf $NDEVICE / >/tmp/backup.txt
　　$REWIND
　　$FSF 5
　　tar -dvf $NDEVICE >> /tmp/backup.txt
　　$REWIND
　　cp /tmp/.LASTFULL /etc/.LASTFULL
　　else
　　# this is not Saturday
　　case $DOW in
　　0)
　　# it's Sunday - nothing to do
　　exit 0
　　;;
　　1)
　　# Monday, Let the tape rewind for the difference verification
　　echo $DATE > /tmp/.LASTINC
　　tar -cvvf $DEVICE --newer `cat /etc/.LASTFULL` / >/tmp/backup.txt
　　cp /tmp/.LASTINC /etc/.LASTINC
　　;;
　　*)
　　# Other Days, must rewind manually and Inspect, -i
　　$EOD
　　echo $DATE >/tmp/.LASTINC
　　tar -cvvf $NDEVICE --newer `cat /etc/.LASTINC` / >/tmp/backup
　　$REWIND
　　$FSF `expr $DOW - 1`
　　echo "************ Verifying ${DAY}'s backup" >> /tmp/backup.txt
　　tar --dvf $NDEVICE >> /tmp/backup.txt
　　cp /tmp/.LASTINC /etc/.LASTINC
　　$REWIND
　　esac
　　fi
　　mail $MAILLIST < /tmp/backup.txt
　　rm -f /tmp/backup.txt
　　# END OF SCRIPT