Here’s a simple script for creating daily zfs snapshots that get rotated every week (so you always have one for Mon, Tues, Wed, etc)
#!/usr/bin/perl
use warnings;
use strict;
my $zfsname = shift || die "Need a filesystem name\n";
my $day = `date`;
$day =~ s/(Sun|Mon|Tue|Wed|Thu|Fri|Sat)[\S\s]+/$1/gi;
my $snapname = "$zfsname\@$day";
my $exist = system("zfs list $snapname");
# if it already exists, delete it
if($exist == 0) {
print "Destroying previous weeks snapshot...";
system("zfs destroy $snapname");
print "done.\n";
}
print "Creating daily snapshot...";
system("zfs snapshot $snapname\n");
print "done.\n";
And here’s the crontab entry:
0 2 * * * /usr/sbin/zsnap.pl pool/zones/lava2019
(replace “pool/zones/lava2019″ with whichever zfs you want a snapshot of)
Easy as cake, you’ll always have a zfs snapshot called <zfsname>@Sun through <zfsname>@Sat to rollback to!
You could go one step further, and loop over the output of ‘zpool list -H -o name’, and do a ‘zfs snapshot -r’. That would do all your filesystems for you at once.
Link | June 2nd, 2007 at 2:56 pm
That would make sense, but in this case I don’t actually want to make snapshots of every filesystem, just the ones I specified. Definitely would be easy to add though.
Link | June 3rd, 2007 at 11:35 am
Here’s a simple quick&dirty script I wrote some time ago. Its status is definitely super-alpha, I would never use it as a crontab entry on my own servers and neither should you
But I think it can be useful as a demonstration for your readers.
I do *not* include an information of how to use it. The script is self-explanatory and someone who doesn’t understand it shouldn’t use it anyway, for his/her own sake
—
#!/bin/bash
# backup_zfssnap.sh, (c) 2007 ralf.ramge@webde.de
BACKUPDIR=”/export/backup/snapshots”
DSTAMP=`date ‘+%y%m%d-%H%M%S’`
FILESYS=$1
DEST=$2
REPLICA=$3
BACKUPNAME=`echo $FILESYS | sed ‘s/\//_/g’`
BACKUPFILE=$BACKUPNAME”-“$DSTAMP”.zfs”
SNAPSHOT=$FILESYS”@backup-“$DSTAMP
if [ ! -d $BACKUPDIR ]; then
echo “Backup Directory doesn’t exist”
exit 1
fi
cd $BACKUPDIR
# Check here if we have 7 backup files, create them if we don’t
COUNT_FILES=`ls -1 $BACKUPNAME* | wc -l`
if [ $COUNT_FILES -le 1 ]; then
for COUNT in 1 2 3 4 5 6 7
do
if [ ! -f $BACKUPNAME”-000000-00000″$COUNT”.zfs” ]; then
touch $BACKUPNAME”-000000-00000″$COUNT”.zfs”
sleep 1
fi
done
fi
# Check here that we have less than 8 backup files
COUNT_FILES=`ls -1 $BACKUPNAME* | wc -l`
if [ $COUNT_FILES -gt 7 ]; then
# echo “More than 7 backup files exist”
# exit 1
while [ $COUNT_FILES -gt 7 ]
do
OLDEST_BACKUP_FILE=`ls -rt1 $BACKUPNAME* | head -1`
rm $OLDEST_BACKUP_FILE
let COUNT_FILES=COUNT_FILES-1
done
fi
# Find the oldest backup file to delete
OLDEST_BACKUP_FILE=`ls -rt1 $BACKUPNAME* | head -1`
# Create the snapshot
zfs snapshot $SNAPSHOT
# Create a filesystem image in the local backup directory
zfs send $SNAPSHOT > $BACKUPDIR”/”$BACKUPFILE
# Check for $2 and, if exists, create a second copy on a remote host for tape archival
if [ ! -z $2 ]; then
`zfs send $SNAPSHOT | ssh root@$2 “cat >$BACKUPDIR/$BACKUPFILE”`
fi
# Check for $3 and, if exists, mirror the filesystem on the remote host
if [ ! -z $3 ]; then
`ssh root@$2 “zfs receive $3
Link | June 5th, 2007 at 12:17 am
Damn, looks like the blog software can’t handle it. Please delete the entry and feel free to contact me, I’ll send you the script by e-mail for inclusion in your blog.
Link | June 5th, 2007 at 12:19 am
Nice script! Thanks! Saved me a having to hash this out myself.
Link | October 16th, 2007 at 8:31 am