[BackupPC-users] creating tar archives

[Paul F. <pg...@fo...>]

hello --

i know that this topic is well trodden, and i did get quite
a bit of info from the archives -- if there's a FAQ i should
read, please be kind.  :-)

i want to periodically move a copy of my backed up data out of the
house.  i bought a large removeable disk to use for this.

i realize that copying the pool is prohibitively expensive, due
to the number of hard links.  i can live with that.  (though it was
kind of a surprise, the first time i tried.  :-)

so what i want is a script which creates a tarball of the current
state of every share, and copies them to my removeable disk. 
using some examples from the archives, i've come up with the
script below.  i'd be happy to trade it in for someone else's
well-tested version, and i'd be equally happy to have someone
critique what i've done.

i'm most concerned with my technique for fetching the number of
the most recent backup -- is my egrep/tail/awk going to do the
trick?  (i read that this will be available more directly
in 2.1 -- correct?)

is there a more effective way to loop through the shares on all
of my hosts, rather than hard-coding the list as i have done?  (i
think i read that this, too, is being addressed in 2.1?)

and is my understanding correct, that BackupPC_tarCreate will
give full contents, whether asked for a full or incremental
backup?

anyway, my script appears below.  any comments welcome...

paul
p.s.  and, since i'm new on the list:  thanks for a _great_ backup
system!  i recommend it whenever the topic comes up.
=---------------------
 paul fox, pg...@fo... (arlington, ma, where it's 34.7 degrees)

-------cut here --------
#!/bin/sh

# mount a specific usb-connected disk on /offsite, create backup
# tarballs there, and unmount


if [ ! -f  /proc/scsi/usb-storage-0/1  ]
then
    echo no usb device found >&2
    exit 1
fi

if ! egrep -q  'Maxtor 5 Model: A300J0' /proc/scsi/scsi
then
    echo wrong usb device found >&2
    exit 1
fi


if ! mount /offsite
then
    echo could not mount sda1 on /offsite
    exit 1
fi

# try to ensure we always unmount
trap "umount /offsite" 0


# rotating date-based backup directories -- must be expunged manually
dir=/offsite/bck/$(date +%Y-%m-%d)

if ! mkdir $dir
then
    echo could not mkdir $dir
    exit 1
fi


# create a tarfile for a share
doit()
{
    if [ $# != 2 ]
    then
	echo doit needs two args:  host and sharename
	exit 1
    fi

    host=$1

    share=$2
    # convert '/' to '-'
    sharename=$(echo $share |  sed -e 's/\//-/g' -e 's/^-//' )
    if [ ! "$sharename" ]  # all gone?  must have been '/'
    then
	sharename=root
    fi

    mkdir -p $dir/$host

    back=$(lastback $host)

    bin/BackupPC_tarCreate -h $host -n $back -s $share / |
    	gzip -c > $dir/$host/$sharename.tgz
}

lastback()
{
    host=$1
    log=/big/backuppc/pc/$host/LOG
    egrep '(full|incr) backup [[:digit:]]+ complete' $log |
	tail -1 | awk '{print $5}'

    
}

# enumerate the hosts, and their shares

doit firethorn /
doit firethorn /var
doit firethorn /var2

doit tumbleweed /
doit tumbleweed /boot

doit grass /
doit grass /boot

doit gutso /
doit gutso /boot
doit gutso /usr2
doit gutso /dos