Small script to take ZFS snapshot periodically and send it to a remote host.

Will be replace by zfSnap soon (many pull request to add a send option), maybe in v2.1.
This commit is contained in:
Jeremy Gardais 2014-11-18 16:06:09 +01:00
parent 2803ad5136
commit 23a711608a
1 changed files with 172 additions and 0 deletions

172
snapsend.sh Executable file
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#!/bin/sh
#
# 2014/11/14 - Initial script creation
#
# Based on snapxfer script by pds from zpool.org
# https://zpool.org/zfs-snapshots-and-remote-replication/
#
# Also main use zfSnap (https://github.com/zfsnap/zfsnap/wiki/zfSnap)
# Must take the 1.x version (tree legacy). Too many changes in the 2.0.0 beta.
# Local ZFS filesystems that will have a snapshot
DATASETS="datastore/vm"
# Destination host for snapshot replication
# The user must have enought rights to use `zfs command`
DHOST="root@192.168.0.100"
# Output logfile
LOGFILE="/var/log/snapsend/snapsend.log"
# Tools that help implement snapshot logic (and transfer soon according the pull-requests)
ZSNAP="/usr/local/bin/zfSnap.sh"
# Administrator's email
MAILADMIN="admin1@localhost,admin2@localhost"
# List of all ZFS snapshot
SNAP_LIST=''
REMOTE_SNAP_LIST=''
# The prefix to add to the previous snapshot's name which is now useless
PREFIXSNAP='done_'
######################################################################
# Functions #
######################################################################
# Returns 0 if snapshot exists
SnapExists() {
SNAP_LIST="${SNAP_LIST:-`zfs list -H -o name -t snapshot`}"
local i
for i in $SNAP_LIST; do
[ "$1" = "$i" ] && return 0
done
return 1
}
# Returns 0 if snapshot exists on the remote host
RemoteSnapExist() {
REMOTE_SNAP_LIST="${REMOTE_SNAP_LIST:-`ssh ${1} zfs list -H -o name -t snapshot`}"
local i
for i in $REMOTE_SNAP_LIST; do
[ "$2" = "$i" ] && return 0
done
return 1
}
######################################################################
# Main logic #
######################################################################
interval=$1
usage()
{
if [ "X${interval}" = "X" ]; then
printf 'Usage: %s (async|hourly|daily|weekly|purge)\n' $(basename $0)
printf '\n'
printf '* Asynchronous DR snapshots are kept for 1 hour\n'
printf '* Hourly snapshots are kept for 1 day\n'
printf '* Daily snapshots are kept for one week\n'
printf '* Weekly snapshots are kept for one month\n'
printf '\n'
exit 1
fi
}
if [ ! -f "${LOGFILE}" ]; then
mkdir -p $(dirname ${LOGFILE})
touch "${LOGFILE}"
fi
case "${interval}" in
'async' )
for dset in $DATASETS
do
# Take snapshots for asynchronouss DR purposes
$ZSNAP -v -s -S -a 1h $dset >> $LOGFILE
# Get the last snapshot name on localhost
LOCALSNAP=$(zfs list -H -o name -t snapshot -r ${dset} | tail -n1 | cut -d@ -f2)
#printf 'Local snapshot: %s\n' ${LOCALSNAP}
# Get the last snapshot name on remote host $DHOST
DHOSTSNAP=$(ssh ${DHOST} zfs list -H -o name -t snapshot -r ${dset} | tail -n1 | cut -d@ -f2)
#printf 'Remote snapshot: %s\n' ${DHOSTSNAP}
# Test if $DHOSTSNAP exist on the local system
# Recompose the full snapshot name with $dset@$DHOSTSNAP
if SnapExists "${dset}@${DHOSTSNAP}"; then
#printf '%s exist on the local system\n' ${DHOSTSNAP}
printf '%s@%s will be send to %s to replace the old snapshot: %s' ${dset} ${LOCALSNAP} ${DHOST} ${DHOSTSNAP} >> $LOGFILE
# Send the snapshot the remote host
# zfs send -I datastore/vm@2014-11-17_11.26.22--1h datastore/vm@2014-11-18_14.19.10--1h | ssh nec02.ipr.univ-rennes1.fr zfs recv datastore/vm
zfs send -I "${DHOSTSNAP}" "${dset}@${LOCALSNAP}" | ssh "${DHOST}" zfs recv "${dset}"
printf ' ... done\n' >> $LOGFILE
else
# Mail admin
printf 'ERROR snapshot %s does not exist on the local system\n' ${DHOSTSNAP} | mail ${MAILADMIN} -s 'snapsend_error'
printf 'ERROR snapshot %s for %s does not exist on the local system\n' ${DHOSTSNAP} ${dset} >> $LOGFILE
fi
# Test if the snapshot was successfully receive on the remote host
if RemoteSnapExist "${DHOST}" "${dset}@${LOCALSNAP}"; then
printf 'SUCCESS: the snapshot %s for %s exist on the remote host (%s)\n' ${LOCALSNAP} ${dset} ${DHOST} >> $LOGFILE
# Rename the useless snapshot for the next purge
zfs rename ${dset}@${DHOSTSNAP} ${dset}@${PREFIXSNAP}${DHOSTSNAP}
else
# Mail admin
printf 'ERROR snapshot %s for %s does not exist on the remote host (%s)\n' ${LOCALSNAP} ${dset} ${DHOST} | mail ${MAILADMIN} -s 'snapsend_error'
printf 'ERROR snapshot %s for %s does not exist on the remote host (%s)\n' ${LOCALSNAP} ${dset} ${DHOST} >> $LOGFILE
fi
done
printf '\n' >> $LOGFILE
;;
'hourly' )
# take snapshots, keep for one day
for dset in $DATASETS
do
$ZSNAP -v -s -S -a 1d $dset >> $LOGFILE
done
printf '\n' >> $LOGFILE
;;
'daily' )
# take snapshots, keep for one week
for dset in $DATASETS
do
$ZSNAP -v -s -S -a 1w $dset >> $LOGFILE
done
# Purge snapshots according to TTL
$ZSNAP -v -s -S -d -p ${PREFIXSNAP} >> $LOGFILE
printf '\n' >> $LOGFILE
;;
'weekly' )
# take snapshots, keep for one month
for dset in $DATASETS
do
$ZSNAP -v -s -S -a 1m $dset >> $LOGFILE
done
printf '\n' >> $LOGFILE
;;
'purge' )
# purge snapshots according to TTL
$ZSNAP -v -s -S -d
;;
* )
usage
;;
esac
exit 0