Random footnotes of Engineering

After my moments of stupidity documented below I decided I'd fix the problem. I've coded up a script that will use zfs send and recv to replicate my home directory. At the moment it's manual, but I'll look into hooking into an automatic system:

#!/bin/bash


USER=fifors

HOST=stormspike.sfbay.sun.com

FS="rpool/export/home"

RS="rpool/zion-home-backup"

MAX_SNAP=15

NOW=`date +%Y%m%d%H%M%S`

INIT=0


set -- `getopt i $*`

if [ $? != 0 ]

then

    echo ${USAGE}

    exit 2

fi


for i in $*

do

    case $i in

	-i) echo Initialising Snapshot backup;

	    INIT=1;

	    shift;

	    continue;;

    esac

done


ALIVE=`ping ${HOST} 2>&1 | grep -c alive`


if [ ${ALIVE} ]

then

	SNAPS=`zfs list -t snapshot |grep "${FS}@" | wc -l | tr -d " "`

	echo Determine incremental

	if [ "${INIT}" == "0" ]

	then

	    ISNAP=`zfs list -t snapshot | grep rpool/export/home@ |tail -1 |cut -d " " -f 1`

	fi


	echo "Creating zfs snapshot ${FS}@${NOW} ..."

	zfs snapshot ${FS}@${NOW} > /dev/null 2> /tmp/error.$$

	if [ $? -ne 0 ]

	then

		echo "Failed ($?)!"

		cat /tmp/error.$$

		rm /tmp/error.$$ 

		exit 1

	else

		echo "Successfully created snapshot: ${FS}@${NOW} !"

	fi

	rm /tmp/error.$$

	if [ ${SNAPS} -ge ${MAX_SNAP} ]

	then

		LAST=`zfs list -t snapshot | grep "${FS}@" | head -1 | awk '{ print $1}'`

		echo "Destroying last snapshot: ${LAST}..."

		zfs destroy ${LAST} > /dev/null 2> /tmp/error.$$

		if [ $? -ne 0 ]

		then

			echo "Failed ($?)!"

			cat /tmp/error.$$

			rm /tmp/error.$$

			exit 1

		else

			echo "Successfully destroyed snapshot: ${LAST} !"

		fi

		rm /tmp/error.$$

	fi


	if [ "${INIT}" == "1" ]

	then

	    echo "Initialising the zfs replication of ${FS}..."

	    zfs send ${FS}@${NOW} | ssh ${USER}@${HOST} pfexec /sbin/zfs recv ${RS}@${NOW}

	else

	    echo "Initiate the zfs send of ${FS}@${NOW} to ${RS}@${NOW}..."

	    zfs send -i ${ISNAP} ${FS}@${NOW} | ssh ${USER}@${HOST} pfexec /sbin/zfs recv -F ${RS}@${NOW}

	fi


	if [ $? -ne 0 ]

	then

		echo "Failed ($?)!"

		exit 1

	else

		echo "Successfully synced snapshot: ${FS}@${NOW} and ${RS}@${NOW} !"

	fi

else

	echo "Cannot connect to ${HOST}"

fi

It's pretty simple really, just relies on the underlying aspects of ZFS to make it all ok.

Grr.. it looks like html destroys the format... I'll fix that later.