FreeNAS 0.7, ZFS snapshots and scrubbing

I've described here how I am doing snapshots. Cron and a little script works perfect, but I also scrub from time to time the zpools. But the scrub never finishes :-(

The reason behind this is described here. Scrubbing or resilvering a pool starts over when a snapshot is taken.

So it is necessary to change the script that creates the snapshots

snapshot_hourly.sh

#!/bin/sh

# If a scrub is running, don't do a snapshot (otherwise scrub will restarts at 0%)

pools=$(zpool list -H -o name)

for pool in $pools;

do

if zpool status -v $pool | grep -q "scrub in progress"; then

exit

fi

done

# Destroy the old snapshot and create the new

zfs destroy $1@hourly.`date "+%H"` > /dev/null 2>&1

zfs snapshot $1@hourly.`date "+%H"`

snapshot_daily.sh

#!/bin/sh

# If a scrub is running, don't do a snapshot (otherwise scrub will restarts at $

pools=$(zpool list -H -o name)

for pool in $pools;

do

if zpool status -v $pool | grep -q "scrub in progress"; then

exit

fi

done

# Destroy the old snapshot and create the new

zfs destroy $1@daily.`date "+%a"` > /dev/null 2>&1

zfs snapshot $1@daily.`date "+%a"`

and snapshot_weekly.sh (please be aware that I use this script to keep snapshots of the last twelve weeks. If necessary, you need to change this...)

#!/bin/sh

# If a scrub is running, don't do a snapshot (otherwise scrub will restarts at $

pools=$(zpool list -H -o name)

for pool in $pools;

do

if zpool status -v $pool | grep -q "scrub in progress"; then

exit

fi

done

# Destroy the oldest snapshot, rotate the other and create the new

zfs destroy $1@weekly.12 > /dev/null 2>&1

zfs rename $1@weekly.11 @weekly.12 > /dev/null 2>&1

zfs rename $1@weekly.10 @weekly.11 > /dev/null 2>&1

zfs rename $1@weekly.9 @weekly.10 > /dev/null 2>&1

zfs rename $1@weekly.8 @weekly.9 > /dev/null 2>&1

zfs rename $1@weekly.7 @weekly.8 > /dev/null 2>&1

zfs rename $1@weekly.6 @weekly.7 > /dev/null 2>&1

zfs rename $1@weekly.5 @weekly.6 > /dev/null 2>&1

zfs rename $1@weekly.4 @weekly.5 > /dev/null 2>&1

zfs rename $1@weekly.3 @weekly.4 > /dev/null 2>&1

zfs rename $1@weekly.2 @weekly.3 > /dev/null 2>&1

zfs rename $1@weekly.1 @weekly.2 > /dev/null 2>&1

zfs snapshot $1@weekly.1

I've found a script from http://hype-o-thetic.com to run a scrub regularly. See his blogpost here...

Just for backup reasons, I post this script below...

#!/bin/bash

#VERSION: 0.2

#AUTHOR: gimpe

#EMAIL: gimpe [at] hype-o-thetic.com

#WEBSITE: http://hype-o-thetic.com

#DESCRIPTION: Created on FreeNAS 0.7RC1 (Sardaukar)

# This script will start a scrub on each ZFS pool (one at a time) and

# will send an e-mail or display the result when everyting is completed.

#CHANGELOG

# 0.2: 2009-08-27 Code clean up

# 0.1: 2009-08-25 Make it work

#SOURCES:

# http://aspiringsysadmin.com/blog/2007/06/07/scrub-your-zfs-file-systems-regularly/

# http://www.sun.com/bigadmin/scripts/sunScripts/zfs_completion.bash.txt

# http://www.packetwatch.net/documents/guides/2009073001.php

# e-mail variables

FROM=from@devnull.com

TO=to@devnull.com

SUBJECT="$0 results"

BODY=""

# arguments

VERBOSE=0

SENDEMAIL=1

args=("$@")

for arg in $args; do

case $arg in

"-v" | "--verbose")

VERBOSE=1

;;

"-n" | "--noemail")

SENDEMAIL=0

;;

"-a" | "--author")

echo "by gimpe at hype-o-thetic.com"

exit

;;

"-h" | "--help" | *)

echo "

usage: $0 [-v --verbose|-n --noemail]

-v --verbose output display

-n --noemail don't send an e-mail with result

-a --author display author info (by gimpe at hype-o-thetic.com)

-h --help display this help

"

exit

;;

esac

done

# work variables

ERROR=0

SEP=" - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - "

RUNNING=1

# commands & configuration

ZPOOL=/sbin/zpool

PRINTF=/usr/bin/printf

MSMTP=/usr/local/bin/msmtp

MSMTPCONF=/var/etc/msmtp.conf

# print a message

function _log {

DATE="`date +"%Y-%m-%d %H:%M:%S"`"

# add message to e-mail body

BODY="${BODY}$DATE: $1\n"

# output to console if verbose mode

if [ $VERBOSE = 1 ]; then

echo "$DATE: $1"

fi

}

# find all pools

pools=$($ZPOOL list -H -o name)

# for each pool

for pool in $pools; do

# start scrub for $pool

_log "starting scrub on $pool"

zpool scrub $pool

RUNNING=1

# wait until scrub for $pool has finished running

while [ $RUNNING = 1 ]; do

# still running?

if $ZPOOL status -v $pool | grep -q "scrub in progress"; then

sleep 60

# not running

else

# finished with this pool, exit

_log "scrub ended on $pool"

_log "`$ZPOOL status -v $pool`"

_log "$SEP"

RUNNING=0

# check for errors

if ! $ZPOOL status -v $pool | grep -q "No known data errors"; then

_log "data errors detected on $pool"

ERROR=1

fi

fi

done

done

# change e-mail subject if there was error

if [ $ERROR = 1 ]; then

SUBJECT="${SUBJECT}: ERROR(S) DETECTED"

fi

# send e-mail

if [ $SENDEMAIL = 1 ]; then

$PRINTF "From:$FROM\nTo:$TO\nSubject:$SUBJECT\n\n$BODY" | $MSMTP --file=$MSMTPCONF -t

fi