This script is usually called from /etc/crontab and requires that you have rsync installed on the system. At the top of the actual script code is a section that you will need to update to specify where you want the backups to go and what directories you want to backup.
#!/usr/bin/perl
#
#
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# Ideas taken from Mike's handy rotating-filesystem-snapshot #
# utility, http://www.mikerubel.org/computers/rsync_snapshots/ #
# and from code written by Eric Ross #
####################################################################
#
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# This program is not guaranteed to work at all, and by using this #
# program you release the author of any an all liability. #
# #
# You may use this program so long as this notice, disclaimer and #
# comment box remain intact and unchanged. #
# #
# Please send me all bugs and patches. #
# #
# Written by Bret Jordan #
# jordan at open1x littledot org #
####################################################################
#
#
#
# Example /etc/crontab
# Every night at 1:01 make rsync copy and then give plenty of time before snapshots
# 01 1 * * * root /local/bin/snapshot rsync
#
# Every night at 2:01 make snapshots
# 01 2 * * * root /local/bin/snapshot snap 7 daily
#
# Every Sunday Morning at 3:01 make weekly snapshot
# 01 3 * * 7 root /local/bin/snapshot snap 4 weekly
#
# First day of every month at 4:01 make monthly snapshot
# 01 4 1 * * root /local/bin/snapshot snap 12 monthly
use 5.8.8;
use strict;
use warnings;
our $VERSION = "0.02";
$VERSION = eval $VERSION;
my $sType = shift;
my $iHistoryLength = shift;
my $sFreq = shift;
########################
# BEGIN THINGS TO UPDATE
my $sSnapDir = "/backups/snapshots";
my $sCurrentBackupDir = "$sSnapDir/backup.current";
my @aDirsToBackup = qw (/data/home/);
# END THIGNS TO UPDATE
########################
unless ($sType eq "rsync" || $sType eq "snap")
{ &ShowSyntax(); }
if ($sType eq "snap")
{
unless ($iHistoryLength =~ /^\d+$/)
{ &ShowSyntax(); }
unless ($sFreq eq "hourly" || $sFreq eq "daily" || $sFreq eq "weekly" || $sFreq eq "monthly")
{ &ShowSyntax(); }
}
sub ShowSyntax
{
print "Please run command with ./snapshot <rsync snap=""> <historylength> <freq name="">\n";
print "Example: ./snapshot 7 daily\n";
print "Example: ./snapshot 24 hourly\n";
die;
}
# Lets make sure we are running at root
unless ( $< == 0 ) { die "This program must be run as root\n"; }
# Do we have write access to the snap directory?
unless ( -w $sSnapDir ) { die "This user does not have write access to $sSnapDir\n"; }
if ($sType eq "rsync")
{
#----------------------------------------
# Rsync Command
#----------------------------------------
#-a = archive mode which is -rlptgoD (no -H,-A,-X)
#
#-r = recurse in to directories
#-l = copy symlinks as symlinks
#-p = preserve permissions
#-t = preserve modification times
#-g = preserve group
#-o = preserve owner
#-D = preserve device files and special files
foreach (@aDirsToBackup) { system("rsync -vax --delete $_ $sCurrentBackupDir"); }
# Touch the directory so the date time is right
system("touch $sCurrentBackupDir");
}
elsif ($sType eq "snap")
{
# Step 1: Delete oldest snap shot and increase the age of the rest
my $i = $iHistoryLength;
while ($i > 0)
{
my $sCurrentDir = "$sSnapDir/backup.$sFreq.$i";
# If index equals the max length of the history, then delete that directory
if ( $i == $iHistoryLength ) { system ("rm -rf $sCurrentDir"); }
else
{
my $j = $i + 1;
my $sNewDir = "$sSnapDir/backup.$sFreq.$j";
if ( -d $sCurrentDir ) { system ("mv $sCurrentDir $sNewDir"); }
}
$i--;
}
# Step 2: Make a hard link from the backup.current to backup.daily.1
unless ( -d $sCurrentBackupDir ) { die "The current backup directory does not exist\n"; }
system("cp -al $sSnapDir/backup.current $sSnapDir/backup.$sFreq.1");
}
