Shell Programming and Scripting

abort()
{
	echo "$1"
	echo "Backup aborted"
	exit
}

#check destination_path
if [ ! -d "$destination_path" ]
then
	abort "Destination path does not exist: $destination_path"
fi
if [ ! -w "$destination_path" ]
then
	abort "Destination path write permission is not granted: $destination_path"
fi

#set destination_path (no spaces allowed)
destination_path="/media/USBdrive/backups/"
destination_path="/media_test/USB drive/backups/"

#! /usr/bin/ksh
######################################### rsyc2usb MANUAL #########################################
#OVER VIEW
#The rsyc2usb script uses rsync to backup files.
#Files that have changed since the previous backup are copied to destination.
#Destination can be on a local HD or USB device.
#Works on FAT and ntfs file systems (most USB flash memories use FAT32).
#Tested on rsync version 3.0.5  protocol version 30; Ubuntu 9.10. 
 
#MAKE BACKUPS
#First customize the four rsync parameters in the section "SET YOUR VARIABLES HERE" (below).
#Backups should be more than one hour apart (because FAT/ntfs uses DST and UNIX does not).
#From Terminal: sudo path/rsyc2usb
#RESTORE
#Restoring files is as simple as a cp command.  Backup files are not compressed.
#Backup folder naming convention is "backup-yymmdd-hhmmss"
#e.g. backup-090511-223344 was made on 2009 May 11 at 22:33:44.
##################################### SET YOUR VARIABLES HERE #####################################
#rsync options from man page on rsync:
#    -r, --recursive
#    -l, --preserve links 
#    -t, --preserve times
#    -x, --one-file-system    don't cross filesystem boundaries
#    -i, --itemize-changes   output a change-summary for all updates
#    -n, --dry-run           perform a trial run with no changes made
#    -v, --verbose
#    --modify-window=3601    allow times to differ by 1 hour and 1 second 
#    (FAT uses DST and UNIX does not DST change and date comparisons)
#    (FAT uses 2-second resolution rsync FAQ)  
#    (FAT does not support options -pgoD, so don't use option -a)
#set options
options="-rltx --modify-window=3601"    #for real backups
##options="-rltxin"            #for testing
#set --exclude-from file (empty string "" means no exclude-from file)
exclude_from=""
#set sources, one line per source, each source in single quotes ('), end each line with space and escape ( \)
sources="\
'/home/brad/muse/' \
"
#set destination_path (no spaces allowed)
destination_path="/media/usb/"
################################### NO NEED TO EDIT CODE BELOW ####################################
#check destination_path
if [[ ! -d "$destination_path" || ! -w "$destination_path" ]]
then
    echo "Destination path does not exist or write permission is not granted:"
    echo "    $destination_path"
    echo "Backup aborted"
  echo
    exit
fi
#find the latest_backup
latest_backup=`eval ls -drX \'$destination_path\'backup-[0-9][0-9][0-1][0-9][0-3][0-9]-[0-2][0-9][0-6][0-9][0-6][0-9] 2>/dev/null| head -1`
#set link_dest
if [ -n "$latest_backup" ]
then
    #only files that have changed since the latest_backup will be copied into destination
    link_dest="--link-dest='$latest_backup'"
else
    #should we make a full backup?
    echo "latest_backup not found.  Make a full backup? (y)"
    read answer
    if [ "$answer" = "y" ]
    then
        link_dest=""
    else
        echo "Backup aborted"
        exit
    fi
fi
#set exclude_from
if [ "$exclude_from" != "" ]
then
    exclude_from="--exclude-from='$exclude_from'"
fi
#set destination (FAT does not allow colon in filename, so use dashes)
destination=\'`date "+${destination_path}backup-%y%m%d-%H%M%S"`\'
#print wait message
echo "  rsync parameters: -"
echo
echo "    options = $options"
echo "    exclude_from = $exclude_from"
echo "    link_dest = $link_dest"
echo "    sources = $sources"
echo "    destination = $destination"
echo `date "+rsync  started at %H:%M:%S. Please do not close this window until rsync is finished."`
echo
#run rsync
EC=$(eval rsync $options $exclude_from $link_dest $sources $destination)
if [[ $EC -eq 0 ]];then
 #print done message
 echo `date "+rsync finished at %H:%M:%S."`
 echo
else
 echo "Failed - rsync failed with exit code ($EC)"
 echo
fi
exit $EC
########################################### END OF FILE ###########################################

ls: cannot access /media/usb/backup-[0-9][0-9][0-1][0-9][0-3][0-9]-[0-2][0-9][0-6][0-9][0-6][0-9]: No such file or directory
latest_backup not found. Make a full backup? (y)

latest_backup not found. Make a full backup? (y)
y

latest_backup not found.  Make a full backup? (y)
y
  rsync parameters: -
    options = -rltx --modify-window=3601
    exclude_from = 
    link_dest = 
    sources = '/home/brad/muse/' 
    destination = '/media/usb/backup-091021-210906'
rsync started at 21:09:06. Please do not close this window until rsync is finished.
rsync finished at 21:09:06.
poweredge:/home/brad/bin>